0001804220-21-000033 | 10-Q | XBRL Viewer | Regeneron Pharmaceuticals INC

Product Sales

Net product sales consist of the following:


(In millions)	Three Months Ended September 30,					Nine Months Ended September 30,
Net Product Sales in the United States	2021			2020		2021			2020
EYLEA®	$	1,473.4		$	1,318.3	$	4,245.1		$	3,604.0
Libtayo®	78.4			71.6		225.5			196.6
Praluent®	44.8			48.5		130.0			95.7		*
REGEN-COV®	676.7			40.2		3,530.1			40.2
Evkeeza®	6.6			—		9.1			—
ARCALYST®	—		**	3.6		2.2		**	9.3
	$	2,279.9		$	1,482.2	$	8,142.0		$	3,945.8

* Effective April 1, 2020, the Company became solely responsible for the development and commercialization of Praluent in the United States and records net product sales of Praluent in the United States. Previously, Sanofi recorded net product sales of Praluent in the United States. See Note 3 for further details.
** Effective April 1, 2021, Kiniksa records net product sales of ARCALYST in the United States. Previously, the Company recorded net product sales of ARCALYST in the United States.

As of September 30, 2021 and December 31, 2020, the Company had $4.086 billion and $3.112 billion, respectively, of trade accounts receivable that were recorded within Accounts receivable, net.

The Company had product sales to certain customers that accounted for more than 10% of total gross product revenue for the three and nine months ended September 30, 2021 and 2020. Sales to each of these customers as a percentage of the Company's total gross product revenue are as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Besse Medical, a subsidiary of AmerisourceBergen Corporation	40	%	50	%	33	%	52	%
McKesson Corporation	24	%	34	%	20	%	34	%
U.S. Government (see Note 3)	25	%	*		38	%	*

* Sales to the U.S. Government represented less than 10% of total gross product revenue during the period.

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Collaboration, License, and Other Agreements

9 Months Ended

Sep. 30, 2021

Collaboration, License, and Other Agreements

a. Sanofi

Amounts recognized in our Statements of Operations in connection with our collaborations with Sanofi are detailed below:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Antibody:
Regeneron's share of profits in connection with commercialization of antibodies	Collaboration revenue	$	387.0	$	212.8	$	975.2	$	555.6
Sales-based milestone earned	Collaboration revenue	$	50.0	$	50.0	$	50.0	$	50.0
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	144.7	$	94.3	$	361.2	$	275.0
Reimbursement of research and development expenses	Reduction of Research and development expense	$	45.2	$	45.5	$	122.3	$	174.4
Regeneron's obligation for its share of Sanofi research and development expenses	Research and development expense	$	(10.3)	$	(17.5)	$	(32.8)	$	(59.1)
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	79.0	$	83.2	$	216.9	$	260.4

Immuno-oncology:
Regeneron's share of losses in connection with commercialization of Libtayo outside the United States	Collaboration revenue	$	(3.0)	$	(4.7)	$	(12.6)	$	(17.3)
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	3.1	$	0.9	$	10.5	$	6.0
Reimbursement of research and development expenses	Reduction of Research and development expense	$	21.8	$	49.8	$	66.2	$	136.7
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	22.8	$	14.5	$	62.0	$	39.2
Regeneron's obligation for its share of Sanofi commercial expenses	Selling, general, and administrative expense	$	(9.4)	$	(6.1)	$	(28.0)	$	(15.0)
Regeneron's obligation for Sanofi's share of Libtayo U.S. gross profits	Cost of goods sold	$	(34.6)	$	(31.5)	$	(99.4)	$	(86.5)
Amounts recognized in connection with up-front payments received	Other operating income	$	(47.7)	$	20.0	$	(4.1)	$	57.0

Antibody

The Company is party to a global, strategic collaboration with Sanofi to research, develop, and commercialize fully human monoclonal antibodies (the "Antibody Collaboration"), which currently consists of Dupixent® (dupilumab), Kevzara® (sarilumab), and itepekimab. Under the terms of the Antibody License and Collaboration Agreement ("LCA"), Sanofi is generally responsible for funding 80%–100% of agreed-upon development costs.

Sanofi leads commercialization activities for products under the Antibody Collaboration, subject to the Company's right to co-commercialize such products. In addition to profit and loss sharing, the Company is entitled to receive sales milestone payments from Sanofi. In the third quarter of 2020, the Company earned, and recognized as revenue, the first $50.0 million sales-based milestone from Sanofi, upon aggregate annual sales of antibodies outside the United States (including Praluent) exceeding $1.0 billion on a rolling twelve-month basis. In the third quarter of 2021, the Company earned, and recognized as revenue, the second $50.0 million sales-based milestone from Sanofi, upon aggregate annual sales of antibodies outside the United States (including Praluent) exceeding $1.5 billion on a rolling twelve-month basis. We are entitled to receive up to an aggregate of $150.0 million in additional sales milestone payments from Sanofi.

The following table summarizes contract balances in connection with the Company's Antibody Collaboration with Sanofi:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	536.0	$	407.7
Deferred revenue	$	431.7	$	347.7

In April 2020, the Company and Sanofi entered into an amendment to the LCA in connection with, among other things, the removal of Praluent from the LCA such that (i) effective April 1, 2020, the LCA no longer governs the development, manufacture, or commercialization of Praluent and (ii) the quarterly period ended March 31, 2020 was the last quarter for which Sanofi and the Company shared profits and losses for Praluent under the LCA. The parties also entered into a Praluent Cross License & Commercialization Agreement (the "Praluent Agreement") pursuant to which, effective April 1, 2020, the Company, at its sole cost, became solely responsible for the development and commercialization of Praluent in the United States, and Sanofi, at its sole cost, became solely responsible for the development and commercialization of Praluent outside of the United States. Under the Praluent Agreement, Sanofi will pay the Company a 5% royalty on Sanofi’s net product sales of Praluent outside the United States until March 31, 2032. The Company will not owe Sanofi royalties on the Company’s net product sales of Praluent in the United States. Although each party will be responsible for manufacturing Praluent for its respective territory, the parties have entered into definitive supply agreements under which, for a certain transitional period, the Company will continue to supply drug substance to Sanofi and Sanofi will continue to supply finished product to Regeneron.

With respect to any intellectual property or product liability litigation relating to Praluent, the parties have agreed that, effective April 1, 2020, Regeneron and Sanofi each will be solely responsible for any such litigation (including damages and other costs and expenses thereof) in the United States and outside the United States, respectively, arising out of Praluent sales or other activities on or after April 1, 2020 (subject to Sanofi's right to set off a portion of any third-party royalty payments resulting from certain patent litigation proceedings against up to 50% of any Praluent royalty payment owed to Regeneron). The parties will each bear 50% of any damages arising out of Praluent sales or other activities prior to April 1, 2020. See Note 12 for discussion of legal proceedings related to Praluent.

Immuno-Oncology

The Company is party to a collaboration with Sanofi to research, develop, and commercialize antibody-based cancer treatments in the field of immuno-oncology (the "IO Collaboration").

Effective December 31, 2018, the Company and Sanofi entered into an Amended and Restated Immuno-oncology Discovery and Development Agreement ("Amended IO Discovery Agreement"), which narrowed the scope of the existing discovery and development activities conducted by the Company under the 2015 IO Discovery Agreement to developing therapeutic bispecific antibodies targeting (i) BCMA and CD3 (the "BCMAxCD3 Program") and (ii) MUC16 and CD3 (the "MUC16xCD3 Program") through clinical proof-of-concept. During the first quarter of 2021, Sanofi did not exercise its options to license rights to these product candidates; as a result, we retain the exclusive right to develop and commercialize such product candidates and Sanofi will receive a royalty on sales (if any). In addition, the Company has no further obligations to develop drug product candidates under the Amended IO Discovery Agreement.

Under the terms of the Immuno-oncology License and Collaboration Agreement, the parties are co-developing and co-commercializing Libtayo (cemiplimab). The parties share equally, on an ongoing basis, agreed-upon development and commercialization expenses for Libtayo. The Company has principal control over the development of Libtayo and leads commercialization activities in the United States (see Note 2 for related product sales information), while Sanofi leads commercialization activities outside of the United States. The parties share equally in profits and losses in connection with the commercialization of Libtayo.

During the three months ended September 30, 2021, we updated our estimate of the total research and development costs expected to be incurred (which resulted in a change to the estimate of the stage of completion) in connection with the IO Collaboration, and, as a result, recorded a cumulative catch-up adjustment of $66.9 million as a reduction to other operating income.

The following table summarizes contract balances in connection with the Company's IO Collaboration with Sanofi:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	0.1	$	(6.5)
Deferred revenue	$	16.2	$	10.7
Other liabilities	$	286.0	$	280.9

Other liabilities include up-front payments received from Sanofi for which recognition has been deferred.

The aggregate amount of the estimated consideration under the IO Collaboration related to the Company's obligation that was unsatisfied (or partially unsatisfied) as of September 30, 2021 was $591.4 million. This amount is expected to be recognized over the remaining period in which the Company is obligated to satisfy its obligation in connection with performing development activities.

b. Bayer

The Company is party to a license and collaboration agreement with Bayer for the global development and commercialization of EYLEA outside the United States. All agreed upon EYLEA development expenses incurred by the Company and Bayer are shared equally. Bayer markets EYLEA outside the United States, where, for countries other than Japan, the companies share equally in profits and losses from sales of EYLEA. In Japan, the Company is currently entitled to receive a tiered percentage of between 33.5% and 40.0% of EYLEA net product sales through 2021, and thereafter, the companies will share equally in profits and losses from sales of EYLEA.

Amounts recognized in our Statements of Operations in connection with our Bayer EYLEA collaboration are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	Collaboration revenue	$	351.0	$	287.9	$	995.3	$	772.6
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	14.0	$	12.0	$	41.6	$	52.9
Reimbursement of research and development expenses	Reduction of Research and development expense	$	14.5	$	11.5	$	35.2	$	34.3
Regeneron's obligation for its share of Bayer research and development expenses	Research and development expense	$	(8.0)	$	(12.9)	$	(31.4)	$	(26.3)

The following table summarizes contract balances in connection with our Bayer EYLEA collaboration:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	374.8	$	336.2
Deferred revenue	$	115.2	$	99.7

c. Teva

The Company and Teva are parties to a collaboration agreement (the "Teva Collaboration Agreement") to develop and commercialize fasinumab globally, excluding certain Asian countries that are subject to our collaboration agreement with Mitsubishi Tanabe Pharma Corporation. The Company leads global development activities, and the parties share development costs equally, on an ongoing basis, under a global development plan.

Amounts recognized in our Statements of Operations in connection with our collaboration with Teva are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Reimbursement of research and development expenses	Reduction of Research and development expense	$	5.1	$	25.9	$	36.6	$	82.1
Amounts recognized in connection with up-front and development milestone payments received	Other operating income	$	3.2	$	17.2	$	22.6	$	54.5

The following table summarizes contract balances in connection with the Teva Collaboration Agreement:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	5.2	$	27.7
Other liabilities	$	43.3	$	66.8

Other liabilities include up-front and development milestone payments received from Teva for which recognition has been deferred.

The aggregate amount of the estimated consideration under the Teva Collaboration Agreement related to the Company's obligation that was unsatisfied (or partially unsatisfied) as of September 30, 2021 was $96.7 million. This amount is expected to be recognized over the remaining period in which the Company is obligated to satisfy its obligation in connection with performing development activities.

d. U.S. Government

REGEN-COV (casirivimab and imdevimab)

In the first quarter of 2020, we announced an expansion of our Other Transaction Agreement with the Biomedical Advanced Research Development Authority ("BARDA"), pursuant to which the U.S. Department of Health and Human Services ("HHS") was obligated to fund certain of our costs incurred for research and development activities related to COVID-19 treatments.

In July 2020, we entered into an agreement with entities acting at the direction of BARDA and the U.S. Department of Defense to manufacture and deliver filled and finished drug product of REGEN-COV to the U.S. government.

In January 2021, the Company announced an agreement with an entity acting on behalf of the U.S. Department of Defense and HHS to manufacture and deliver additional filled and finished drug product of REGEN-COV to the U.S. government. Pursuant to the agreement, the U.S. government was obligated to purchase the 1.25 million doses of drug product that we delivered by June 30, 2021.

The Company has completed its final deliveries of drug product under the agreements described above.

In September 2021, the Company announced an amendment to its January 2021 agreement to supply the U.S. government with an additional 1.4 million doses of REGEN-COV. Pursuant to the agreement, the U.S. government is obligated to purchase all filled and finished doses of such additional drug product delivered by January 31, 2022, resulting in payments to the Company of up to $2.940 billion in the aggregate. Additionally, Roche will supply a portion of the doses to Regeneron to fulfill our agreement with the U.S. government (see "Roche" below for further details regarding our collaboration agreement with Roche).

See Note 2 for REGEN-COV net product sales recognized in connection with these agreements.

e. Roche

In August 2020, we entered into a collaboration agreement (the "Roche Collaboration Agreement") with Roche to develop, manufacture, and distribute the casirivimab and imdevimab antibody cocktail (known as REGEN-COV in the United States and Ronapreve™ in other countries). We lead global development activities for casirivimab and imdevimab, and the parties jointly fund certain ongoing studies, as well as any mutually agreed additional new global studies to evaluate further the potential of casirivimab and imdevimab in treating or preventing COVID-19.

Under the terms of the agreement, each party is obligated to dedicate a certain amount of manufacturing capacity to casirivimab and imdevimab each year. We distribute the product in the United States and Roche distributes the product outside of the United States. The parties share gross profits from worldwide sales based on a pre-specified formula, depending on the amount of manufactured product supplied by each party to the market. Each quarter, a single payment is due from one party to the other to true-up the global gross profits between the parties. If Regeneron is to receive a true-up payment from Roche, such amount will be recorded to Collaboration revenue. If Regeneron is to make a true-up payment to Roche, such amount will be recorded to Cost of goods sold.

Amounts recognized in our Statements of Operations in connection with the Roche Collaboration Agreement are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Global gross profit true-up payment owed from Roche in connection with sales of casirivimab and imdevimab	Collaboration revenue	$	127.1	—		$	361.8	—
Reimbursement of research and development expenses	Reduction of Research and development expense	$	10.5	$	9.5	$	138.3	$	9.5

The following table summarizes contract balances in connection with the Roche Collaboration Agreement:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	305.5	$	77.1

f. Intellia

In 2016, we entered into a license and collaboration agreement with Intellia Therapeutics, Inc. to advance CRISPR/Cas9 gene-editing technology for in vivo therapeutic development. The parties collaborate to conduct research for the discovery, development, and commercialization of new therapies, in addition to the research and technology development of the CRISPR/Cas9 platform.

In May 2020, we expanded our existing collaboration with Intellia to provide us with rights to develop products for additional in vivo CRISPR/Cas9-based therapeutic targets and for the parties to jointly develop potential products for the treatment of hemophilia A and B. In addition, we also received non-exclusive rights to independently develop and commercialize ex vivo gene edited products. In connection with the agreement, we made a $70.0 million up-front payment and purchased shares of Intellia common stock for an aggregate purchase price of $30.0 million. The up-front payment and the amount paid in excess of the fair market value of the shares purchased, or $15.0 million, were recorded to Research and development expense during the three months ended June 30, 2020.

Net Income Per Share

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Net Income Per Share

Basic net income per share is computed by dividing net income by the weighted average number of shares of Common Stock and Class A Stock outstanding. Net income per share is presented on a combined basis, inclusive of Common Stock and Class A Stock outstanding, as each class of stock has equivalent economic rights. Diluted net income per share includes the potential dilutive effect of other securities as if such securities were converted or exercised during the period, when the effect is dilutive. The calculations of basic and diluted net income per share are as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions, except per share data)	2021		2020		2021		2020
Net income - basic and diluted	$	1,632.2	$	842.1	$	5,846.3	$	2,364.0

Weighted average shares - basic	106.2		105.5		105.5		108.3
Effect of dilutive securities:
Stock options	6.4		7.8		5.3		7.3
Restricted stock awards and restricted stock units	1.3		0.6		1.0		0.5
Weighted average shares - diluted	113.9		113.9		111.8		116.1

Net income per share - basic	$	15.37	$	7.98	$	55.42	$	21.83
Net income per share - diluted	$	14.33	$	7.39	$	52.29	$	20.36

Shares which have been excluded from diluted per share amounts because their effect would have been antidilutive include the following:


	Three Months Ended September 30,		Nine Months Ended September 30,
(Shares in millions)	2021	2020	2021	2020
Stock options	0.4	0.1	4.8	2.6

Marketable Securities

9 Months Ended

Sep. 30, 2021

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

Marketable securities as of September 30, 2021 and December 31, 2020 consist of both available-for-sale debt securities of investment grade issuers (see below and Note 6) as well as equity securities of publicly traded companies (see Note 6).

The following tables summarize the Company's investments in available-for-sale debt securities:


(In millions)	Amortized		Unrealized				Fair
As of September 30, 2021	Cost Basis		Gains		Losses		Value
Corporate bonds	$	5,911.8	$	19.9	$	(6.9)	$	5,924.8
U.S. government and government agency obligations	101.2		0.6		(0.1)		101.7
Sovereign bonds	64.6		0.5		—		65.1
Commercial paper	272.6		—		—		272.6
Certificates of deposit	231.7		—		—		231.7
Asset-backed securities	19.0		—		—		19.0
	$	6,600.9	$	21.0	$	(7.0)	$	6,614.9

As of December 31, 2020
Corporate bonds	$	3,053.0	$	37.5	$	(0.2)	$	3,090.3
U.S. government and government agency obligations	127.6		1.3		—		128.9
Sovereign bonds	65.2		1.1		—		66.3
Commercial paper	276.0		0.1		—		276.1
Certificates of deposit	127.4		0.1		—		127.5
	$	3,649.2	$	40.1	$	(0.2)	$	3,689.1

The Company classifies its investments in available-for-sale debt securities based on their contractual maturity dates. The available-for-sale debt securities listed as of September 30, 2021 mature at various dates through September 2026. The fair values of available-for-sale debt securities by contractual maturity consist of the following:


	September 30,		December 31,
(In millions)	2021		2020
Maturities within one year	$	2,355.2	$	1,393.3
Maturities after one year through five years	4,259.7		2,295.8
	$	6,614.9	$	3,689.1

The following table shows the fair value of the Company's available-for-sale debt securities that have unrealized losses, aggregated by investment category and length of time that the individual securities have been in a continuous loss position.


	Less than 12 Months				12 Months or Greater		Total
(In millions) As of September 30, 2021	Fair Value		Unrealized Loss		Fair Value	Unrealized Loss	Fair Value		Unrealized Loss
Corporate bonds	$	2,905.9	$	(6.9)	—	—	$	2,905.9	$	(6.9)
U.S. government and government agency obligations	27.0		(0.1)		—	—	27.0		(0.1)
	$	2,932.9	$	(7.0)	—	—	$	2,932.9	$	(7.0)

As of December 31, 2020
Corporate bonds	$	364.5	$	(0.2)	—	—	$	364.5	$	(0.2)

For the three and nine months ended September 30, 2021, realized gains and losses on sales of marketable securities were not material. For the three months ended September 30, 2020, realized gains and losses on sales of marketable securities were not material. Realized gains were $28.5 million and realized losses were not material for the nine months ended September 30, 2020.

With respect to marketable securities, for the three and nine months ended September 30, 2021 and 2020, amounts reclassified from Accumulated other comprehensive income into Other (expense) income, net were related to realized gains and losses on sales of available-for-sale debt securities.

Fair Value Measurements

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements

The table below summarizes the Company's assets which are measured at fair value on a recurring basis. The following fair value hierarchy is used to classify assets, based on inputs to valuation techniques utilized to measure fair value:

•Level 1 - Quoted prices in active markets for identical assets

•Level 2 - Significant other observable inputs, such as quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, or model-based valuations in which significant inputs used are observable

•Level 3 - Significant other unobservable inputs


(In millions)			Fair Value Measurements at Reporting Date
As of September 30, 2021	Fair Value		Level 1		Level 2
Available-for-sale debt securities:
Corporate bonds	$	5,924.8	—		$	5,924.8
U.S. government and government agency obligations	101.7		—		101.7
Sovereign bonds	65.1		—		65.1
Commercial paper	272.6		—		272.6
Certificates of deposit	231.7		—		231.7
Asset-backed securities	19.0		—		19.0
Equity securities (unrestricted)	35.7		$	35.7	—
Equity securities (restricted)	1,335.9		1,335.9		—
	$	7,986.5	$	1,371.6	$	6,614.9

As of December 31, 2020
Available-for-sale debt securities:
Corporate bonds	$	3,090.3	—		$	3,090.3
U.S. government and government agency obligations	128.9		—		128.9
Sovereign bonds	66.3		—		66.3
Commercial paper	276.1		—		276.1
Certificates of deposit	127.5		—		127.5
Equity securities (unrestricted)	48.3		$	48.3	—
Equity securities (restricted)	791.5		791.5		—
	$	4,528.9	$	839.8	$	3,689.1

The Company held certain restricted equity securities as of September 30, 2021 which are subject to transfer restrictions that expire at various dates through 2024.

During the three and nine months ended September 30, 2021, we recorded $29.1 million of net unrealized losses and $523.8 million of net unrealized gains, respectively, on equity securities in Other (expense) income, net. During the three and nine months ended September 30, 2020, we recorded $37.5 million of net unrealized losses and $133.8 million of net unrealized gains, respectively, on equity securities in Other (expense) income, net.

In addition to the investments summarized in the table above, as of September 30, 2021 and December 31, 2020, the Company had $40.0 million and $59.2 million, respectively, in equity investments that do not have a readily determinable fair value. These investments are recorded within Other noncurrent assets.

The fair value of our long-term debt (see Note 8), which was determined based on Level 2 inputs, was estimated to be $1.891 billion and $1.958 billion as of September 30, 2021 and December 31, 2020, respectively.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Inventories

9 Months Ended

Sep. 30, 2021

Inventory Disclosure [Abstract]

Inventories

Inventories consist of the following:


	September 30,		December 31,
(In millions)	2021		2020
Raw materials	$	646.3	$	459.4
Work-in-process	843.7		904.6
Finished goods	60.1		121.7
Deferred costs	503.7		430.9
	$	2,053.8	$	1,916.6

Deferred costs represent the costs of product manufactured and shipped to the Company's collaborators for which recognition of revenue has been deferred. For the three and nine months ended September 30, 2021, Cost of goods sold included inventory write-offs and reserves totaling $38.7 million and $188.0 million, respectively. For the three and nine months ended September 30, 2020, Cost of goods sold included inventory write-offs and reserves totaling $11.8 million and $23.6 million, respectively.

Debt

9 Months Ended

Sep. 30, 2021

Debt Disclosure [Abstract]

Debt

Bridge Loan Facility

As described in Note 10, in the second quarter of 2020, we purchased shares of our Common Stock from Sanofi in connection with Sanofi's secondary offering of our Common Stock held by Sanofi. This purchase was partially funded with proceeds from loans under a $1.5 billion senior unsecured bridge loan facility (the "Bridge Facility") which was entered into in May 2020. The loans under the Bridge Facility bore interest at a variable interest rate based on either the London Interbank Offered Rate or the alternate base rate, plus an applicable margin that varied with our debt rating and total leverage ratio. The Bridge Facility was repaid in full during the third quarter of 2020 following the closing of the issuance and sale of the Company's senior notes (as described below).

Senior Notes

In August 2020, we issued and sold $1.250 billion aggregate principal amount of senior unsecured notes due 2030 and $750 million aggregate principal amount of senior unsecured notes due 2050. Long-term debt in connection with our senior unsecured notes (collectively, the "Notes"), net of underwriting discounts and offering expenses, consists of the following:


	September 30,		December 31,
(In millions)	2021		2020
1.750% Senior Notes due September 2030	$	1,239.6	$	1,238.7
2.800% Senior Notes due September 2050	740.0		739.8
	$	1,979.6	$	1,978.5

Interest expense related to the Notes for the three and nine months ended September 30, 2021 was $11.1 million and $33.3 million, respectively.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1E
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income TaxesThe Company is subject to U.S. federal, state, and foreign income taxes. The Company's effective tax rate was 10.2% and 15.6% for the three months ended September 30, 2021 and 2020, respectively, and 14.3% and 8.6% for the nine months ended September 30, 2021 and 2020, respectively. The Company's effective tax rate for the three and nine months ended September 30, 2021 was positively impacted, compared to the U.S. federal statutory rate, primarily by stock-based compensation, income earned in foreign jurisdictions with tax rates lower than the U.S. federal statutory rate, the foreign-derived intangible income deduction, and federal tax credits for research activities. In addition, the effective tax rate for the nine months ended September 30, 2021 was positively impacted by the reversal of liabilities related to uncertain tax positions. During the nine months ended September 30, 2021, we reduced the amount of liabilities for uncertain tax positions related to the Company’s federal income tax returns for 2015 and 2016, as these audits are effectively settled. The Company's federal income tax returns for 2017 and 2018 are currently under audit by the Internal Revenue Service ("IRS"). The Company's effective tax rate for the three and nine months ended September 30, 2020 was positively impacted, compared to the U.S. federal statutory rate, primarily by stock-based compensation, and, to a lesser extent, income earned in foreign jurisdictions with tax rates lower than the U.S. federal statutory rate and federal tax credits for research activities.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Stockholders' Equity

9 Months Ended

Sep. 30, 2021

Equity [Abstract]

Stockholders' Equity

Share Repurchase Programs

In November 2019, our board of directors authorized a share repurchase program to repurchase up to $1.0 billion of our Common Stock. The share repurchase program permitted the Company to effect repurchases through a variety of methods, including open-market transactions (including pursuant to a trading plan adopted in accordance with Rule 10b5-1 of the Exchange Act), privately negotiated transactions, accelerated share repurchases, block trades, and other transactions in compliance with Rule 10b-18 of the Exchange Act. As of December 31, 2020, the Company had repurchased the entire $1.0 billion it was authorized to repurchase under the program.

In January 2021, our board of directors authorized an additional share repurchase program to repurchase up to $1.5 billion of our Common Stock. The share repurchase program was approved under terms substantially similar to the November 2019 share repurchase program described above. Repurchases may be made from time to time at management’s discretion, and the timing and amount of any such repurchases will be determined based on share price, market conditions, legal requirements, and other relevant factors. The program has no time limit and can be discontinued at any time. There can be no assurance as to the timing or number of shares of any repurchases in the future. As of September 30, 2021, $697.3 million remained available for share repurchases under the program.

The table below summarizes the shares of our Common Stock we repurchased under the programs during the three and nine months ended September 30, 2021 and 2020 and the cost of the shares received, which were recorded as Treasury Stock.


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2021		2020		2021		2020
Number of shares repurchased	0.3		0.2		1.6		0.9
Total cost of shares received	$	190.5	$	100.4	$	802.7	$	373.3

Sanofi Funding of Certain Development Costs

In 2018, the Company and Sanofi entered into a letter agreement (the "Letter Agreement") in connection with, among other matters, the allocation of additional funds to certain activities relating to dupilumab and itepekimab (collectively, the "Dupilumab/Itepekimab Eligible Investments"). Pursuant to the Letter Agreement, we agreed to allow Sanofi to satisfy its funding obligations with respect to Dupilumab/Itepekimab Eligible Investments, as well as Libtayo development costs, for quarterly periods ending on September 30, 2020 by selling our Common Stock owned by Sanofi. During the nine months ended September 30, 2020, Sanofi elected to sell, and we elected to purchase (by issuing a credit towards the amount owed by Sanofi), 77,677 shares of our Common Stock to satisfy Sanofi's funding obligation related to Libtayo development costs, and we recorded the cost of the shares received, or $41.7 million, as Treasury Stock. During the nine months ended September 30, 2020, Sanofi elected to sell, and we elected to purchase (in cash), 171,471 shares of our Common Stock in connection with Sanofi's funding obligation for Dupilumab/Itepekimab Eligible Investments, and we recorded the cost of the shares received, or $93.3 million, as Treasury Stock. During the three months ended September 30, 2020, there were no shares of our Common Stock purchased from Sanofi to satisfy Sanofi's funding obligations related to Libtayo development costs and/or Dupilumab/Itepekimab Eligible Investments.

Additional Stock Purchased from Sanofi

In May 2020, a secondary offering of 13,014,646 shares of our Common Stock (the "Secondary Offering") held by Sanofi was completed. In connection with the Secondary Offering, we also purchased 9,806,805 shares directly from Sanofi for an aggregate purchase amount of $5.0 billion (the "Stock Purchase"). As a result of the Secondary Offering and the Stock Purchase, Sanofi disposed of all of its shares of our Common Stock, other than 400,000 shares that it retained as of the closing of the Secondary Offering and the Stock Purchase (a portion of which Sanofi used for the funding of certain Libtayo development costs and/or Dupilumab/Itepekimab Eligible Investments as described above).

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI http://asc.fasb.org/topic&trid=2208762

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Cash and Cash Equivalents [Abstract]

Statement of Cash Flows

9 Months Ended

Sep. 30, 2021

Statement of Cash Flows

The following provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Condensed Consolidated Balance Sheet to the total of the same such amounts shown in the Condensed Consolidated Statement of Cash Flows:


	September 30,
(In millions)	2021		2020
Cash and cash equivalents	$	3,432.4	$	1,573.0
Restricted cash included in Other noncurrent assets	12.5		13.6
Total cash, cash equivalents, and restricted cash shown in the Condensed Consolidated Statement of Cash Flows	$	3,444.9	$	1,586.6

Restricted cash consists of amounts held by financial institutions pursuant to contractual arrangements.

Supplemental disclosure of non-cash investing and financing activities

The following amounts were included in accounts payable, accrued expenses, and other liabilities:


	September 30,		December 31,		September 30,		December 31,
(In millions)	2021		2020		2020		2019
Accrued capital expenditures	$	70.1	$	83.6	$	100.4	$	133.7

Legal Matters	9 Months Ended
Legal Matters	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	Legal Matters From time to time, the Company is a party to legal proceedings in the course of the Company's business. Costs associated with the Company's involvement in legal proceedings are expensed as incurred. The outcome of any such proceedings, regardless of the merits, is inherently uncertain. The Company recognizes accruals for loss contingencies associated with such proceedings when it is probable that a liability will be incurred and the amount of loss can be reasonably estimated. As of September 30, 2021 and December 31, 2020, the Company's accruals for loss contingencies were not material. If the Company were unable to prevail in any such proceedings, its consolidated financial position, results of operations, and future cash flows may be materially impacted. Proceedings Relating to Praluent (alirocumab) Injection As described in greater detail below, the Company is currently a party to patent infringement actions initiated by Amgen Inc. (and/or its affiliated entities) against the Company and/or Sanofi (and/or the Company's and Sanofi's respective affiliated entities) in a number of jurisdictions relating to Praluent. See Note 3 for a description of the Company's and Sanofi's arrangement regarding the costs resulting from or associated with such actions. United States In the United States, Amgen asserted claims of U.S. Patent Nos. 8,829,165 (the "'165 Patent") and 8,859,741 (the "'741 Patent"), and sought a permanent injunction to prevent the Company and the Sanofi defendants from commercial manufacturing, using, offering to sell, or selling within the United States (as well as importing into the United States) (collectively, "Commercializing") Praluent. Amgen also sought a judgment of patent infringement of the asserted patents, monetary damages (together with interest), costs and expenses of the lawsuits, and attorneys' fees. As described in greater detail under "Second Jury Trial and Appeal" below, on February 11, 2021, the Federal Circuit (as defined below) affirmed the lower court's decision that certain of Amgen's asserted patent claims are invalid based on lack of enablement. First Jury Trial and Appeal. The first jury trial in this litigation (the "First Trial") was held in the United States District Court for the District of Delaware (the "District Court") from March 8 to March 16, 2016. During the course of the First Trial, the District Court ruled as a matter of law in favor of Amgen that the asserted patent claims were not obvious, and in favor of the Company and the Sanofi defendants that there was no willful infringement of the asserted patent claims by the Company or the Sanofi defendants. On March 16, 2016, the jury returned a verdict in favor of Amgen in the First Trial, finding that the asserted claims of the '165 and '741 Patents were not invalid based on either a lack of written description or a lack of enablement. On October 5, 2017, the United States Court of Appeals for the Federal Circuit (the "Federal Circuit") reversed in part the District Court's decision and remanded for a new trial on the issues of written description and enablement. In addition, it affirmed the District Court's ruling that Amgen's patents were not obvious. Second Jury Trial and Appeal. On January 3, 2019, the District Court held oral argument in the remanded proceedings on the Company and the Sanofi defendants' motion for judgment on the pleadings regarding Amgen's willful infringement claim. On January 18, 2019, the District Court entered an order (i) denying the Company and the Sanofi defendants' motion for summary judgment on validity, (ii) denying Amgen's motion for partial summary judgment on estoppel, and (iii) granting the Company and the Sanofi defendants' cross-motion for summary judgment on estoppel. On February 8, 2019, the District Court granted the Company and the Sanofi defendants' motion for judgment on the pleadings, thereby dismissing Amgen's claim of willful infringement. The second jury trial in this litigation (the "Second Trial") was held before the District Court in February 2019 to determine the validity of Amgen's asserted patent claims. On February 25, 2019, the jury returned a verdict in the Second Trial generally in favor of Amgen, finding that two claims of the '165 Patent and one claim of the '741 Patent were not invalid. The jury also found that two claims of the '165 Patent were invalid for lack of adequate written description while rejecting the lack of enablement challenges to those two claims. On August 28, 2019, the District Court ruled as a matter of law that Amgen's asserted patent claims are invalid based on lack of enablement. The District Court also conditionally denied the Company and the Sanofi defendants' motion for a new trial. On October 23, 2019, Amgen filed a notice of appeal of the District Court's decision with the Federal Circuit. An oral hearing before the Federal Circuit was held on December 9, 2020. On February 11, 2021, the Federal Circuit affirmed the District Court's decision that certain of Amgen's asserted patent claims are invalid based on lack of enablement. On April 14, 2021, Amgen filed a petition for a rehearing en banc, which was denied on June 21, 2021. Injunctive Relief Proceedings. On March 18, 2019, Amgen filed a renewed motion for a permanent injunction to prohibit the Company and the Sanofi defendants from Commercializing Praluent in the United States (a "Permanent Injunction"), and an oral hearing on this motion was held in June 2019. Previously, the Federal Circuit stayed and then vacated a Permanent Injunction granted by the District Court in connection with the First Trial. On August 28, 2019, the District Court dismissed as moot Amgen's renewed motion for a Permanent Injunction. Europe Amgen has asserted European Patent No. 2,215,124 (the "'124 Patent"), which pertains to PCSK9 monoclonal antibodies, in the countries in Europe discussed below. In October 2020, the '124 Patent claims directed to compositions of matter and medical use relevant to Praluent were ruled invalid based on a lack of inventive step by the Technical Board of Appeal (the "TBA") of the European Patent Office (the "EPO"). This decision impacted each of the infringement proceedings based on the '124 Patent discussed below. Amgen filed lawsuits in Germany, the United Kingdom, and France in July 2016, July 2016, and September 2016, respectively, against the Company and certain of Sanofi's affiliated entities for infringement of the relevant designation of the '124 Patent in each such jurisdiction; and these lawsuits were dismissed in November 2020, September 2021, and June 2021, respectively. The dismissal in Germany followed an earlier finding of infringement and granting of an injunction, both of which were subsequently overturned. In December 2019, Amgen also filed lawsuits in the Netherlands, Italy, and Spain for infringement of the relevant designation of the '124 Patent in each such jurisdiction; the Company was not named as a defendant in any of these actions, and each of these lawsuits was dismissed in February 2021. Japan As previously reported, on March 31, 2020, Amgen filed a lawsuit in the Tokyo District Court against Sanofi K.K. seeking damages incurred by Amgen as a result of the earlier finding of infringement of Amgen's Japanese Patent Nos. 5,906,333 and 5,705,288 by the Tokyo District Court Civil Division. The Company has not been named as a defendant in this damages action. Proceedings Relating to Dupixent (dupilumab) Injection United States On March 23, 2017, the Company, Sanofi-Aventis U.S. LLC, and Genzyme Corporation initiated an inter partes review ("IPR") in the United States Patent and Trademark Office ("USPTO") seeking a declaration of invalidity of U.S. Patent No. 8,679,487 (the "'487 Patent") owned by Immunex Corporation relating to antibodies that bind the human interleukin-4 receptor and subsequently filed two additional IPR petitions in the USPTO seeking declarations of invalidity of the '487 Patent based on different grounds (the "Additional IPR Petitions"). The Patent Trial and Appeal Board ("PTAB") of the USPTO issued a final written decision on the Additional IPR Petitions on February 14, 2019, invalidating all 17 claims of the '487 Patent as obvious. This decision was subsequently affirmed by the Federal Circuit and Immunex's petition for writ of certiorari was denied by the United States Supreme Court. The '487 Patent expired in May 2020 following Immunex's filing of a terminal disclaimer with the USPTO. On April 5, 2017, Immunex Corporation filed a lawsuit against the Company, Sanofi, Sanofi-Aventis U.S. LLC, Genzyme Corporation, and Aventisub LLC in the United States District Court for the Central District of California seeking a judgment of patent infringement of the '487 Patent and a declaratory judgment of infringement of the '487 Patent, in each case by the Company's and the other defendants' Commercializing of Dupixent; monetary damages (together with interest); an order of willful infringement of the '487 Patent, which would allow the court in its discretion to award damages up to three times the amount assessed; costs and expenses of the lawsuit; and attorneys' fees. The court subsequently granted a joint stipulation by the parties to stay the litigation pending resolution of the appeals of the PTAB's final written decisions on the Additional IPR Petitions discussed above; and, on August 3, 2021, granted a motion to dismiss the lawsuit, dismissing all of Immunex's claims with prejudice. Europe On September 30, 2016, Sanofi initiated a revocation proceeding in the United Kingdom to invalidate the U.K. counterpart of European Patent No. 2,292,665 (the "'665 Patent"), another patent owned by Immunex relating to antibodies that bind the human interleukin-4 receptor. At the joint request of the parties to the revocation proceeding, the U.K. Patents Court ordered on January 30, 2017 that the revocation action be stayed pending the final determination of the currently pending EPO opposition proceedings initiated by the Company and Sanofi in relation to the '665 Patent. The oral hearing before the EPO on the oppositions occurred on November 20, 2017, at which the claims of the '665 Patent were found invalid and the patent was revoked. A final written decision of revocation of the '665 Patent was issued by the EPO on January 4, 2018. Immunex filed a notice of appeal of the EPO's decision on January 31, 2018, and an oral hearing before the TBA has been scheduled for March 2022. On September 20, 2017 and September 21, 2017, respectively, the Company and Sanofi initiated opposition proceedings in the EPO against Immunex's European Patent No. 2,990,420 (the "'420 Patent"), a divisional patent of the '665 Patent (i.e., a patent that shares the same priority date, disclosure, and patent term of the parent '665 Patent but contains claims to a different invention). The oral hearing before the EPO on the oppositions occurred on February 14–15, 2019, at which the '420 Patent was revoked in its entirety. Immunex filed a notice of appeal of the EPO's decision on May 31, 2019, and an oral hearing before the TBA has been scheduled for March 2022. The original patent term of the Immunex patents expired in May 2021. Proceedings Relating to EYLEA (aflibercept) Injection On January 7, 2021, Chengdu Kanghong Pharmaceutical Group Co., Ltd. ("Chengdu Kanghong") filed an IPR petition in the USPTO against the Company' s U.S. Patent No. 10,464,992 (the "'992 Patent") and a post-grant review ("PGR") petition against the Company's U.S. Patent No. 10,828,345 (the "'345 Patent") seeking declarations of invalidity of the '992 Patent and '345 Patent. On June 23, 2021, Chengdu Kanghong filed motions to dismiss each of these petitions and terminate the respective proceedings, which were granted by the USPTO on June 25, 2021. On February 11, 2020, anonymous parties filed two requests for ex parte reexamination of the Company's U.S. Patent No. 10,406,226 and the '992 Patent, and the USPTO has granted both requests to initiate reexamination proceedings. On May 5, 2021, Mylan Pharmaceuticals Inc. filed IPR petitions in the USPTO against the Company's U.S. Patent Nos. 9,254,338 (the "'338 Patent") and 9,669,069 (the "'069 Patent") seeking declarations of invalidity of the '338 Patent and the '069 Patent. On September 7, 2021, Celltrion, Inc. filed a PGR petition in the USPTO against the Company's U.S. Patent No. 10,857,231 (the "'231 Patent") seeking a declaration of invalidity of the '231 Patent. On October 26 and October 27, 2021, anonymous parties initiated opposition proceedings in the EPO against the Company's European Patent No. 2,944,306 (the "'306 Patent") seeking revocation of the '306 Patent in its entirety. Proceedings Relating to EYLEA (aflibercept) Injection Pre-filled Syringe On June 19, 2020, Novartis Pharma AG, Novartis Pharmaceuticals Corporation, and Novartis Technology LLC (collectively, "Novartis") filed a complaint with the U.S. International Trade Commission (the "ITC") pursuant to Section 337 of the Tariff Act of 1930 requesting that the ITC institute an investigation relating to the importation into the United States and/or sale within the United States after importation of EYLEA pre-filled syringes ("PFS") and/or components thereof which allegedly infringe Novartis’s U.S. Patent No. 9,220,631 (the "'631 Patent"). Novartis also requested a permanent limited exclusion order forbidding entry into the United States of EYLEA PFS or components thereof; a permanent cease-and-desist order from the importation, sale, offer for sale, advertising, packaging, or solicitation of any sale by the Company of EYLEA PFS or components thereof; and a bond should the Company continue to import EYLEA PFS (if found to infringe) during, if applicable, any 60-day Presidential review period (i.e., the period when the President of the United States (or his designee) can disapprove any ITC decision to issue an exclusion order or cease-and-desist order). The ITC instituted the investigation on July 22, 2020 and a trial was scheduled for April 19–23, 2021. On March 26, 2021, the staff attorney appointed by the ITC's Office of Unfair Import Investigations ("OUII")—an independent government party to the case representing the public interest— determined that the '631 Patent is invalid on several grounds. On April 8, 2021, Novartis moved to terminate the ITC investigation in its entirety based on its withdrawal of the complaint; and, on May 3, 2021, the ITC terminated the investigation. On June 19, 2020, Novartis also filed a patent infringement lawsuit (as amended on August 2, 2021) in the U.S. District Court for the Northern District of New York asserting claims of the '631 Patent and seeking preliminary and permanent injunctions to prevent the Company from continuing to infringe the '631 Patent. Novartis also seeks a judgment of patent infringement of the '631 Patent, monetary damages (together with interest), an order of willful infringement of the '631 Patent (which would allow the court in its discretion to award damages up to three times the amount assessed), costs and expenses of the lawsuits, and attorneys' fees. On July 30, 2020, the court granted the Company's motion to stay these proceedings until a determination in the ITC proceedings discussed above, including any appeals therefrom, becomes final. On June 11, 2021, the court, at the request of Novartis, lifted the stay. On July 16, 2020, the Company initiated two IPR petitions in the USPTO seeking a declaration of invalidity of the '631 Patent on two separate grounds. On January 15, 2021, the USPTO declined to institute an IPR proceeding on procedural grounds in light of the pending ITC investigation discussed above; the other IPR petition has been withdrawn. Following Novartis's motion to terminate the ITC investigation discussed above, on April 16, 2021 the Company filed a new IPR petition seeking a declaration of invalidity of the '631 Patent based on the same grounds that were the basis for the OUII staff attorney's determination discussed above. On October 26, 2021, the USPTO issued a decision instituting the IPR proceeding. On July 17, 2020, the Company filed an antitrust lawsuit against Novartis and Vetter Pharma International Gmbh ("Vetter") in the United States District Court for the Southern District of New York seeking a declaration that the '631 Patent is unenforceable and a judgment that the defendants' conduct violates Sections 1 and 2 of the Sherman Antitrust Act of 1890, as amended (the "Sherman Antitrust Act"). The Company is also seeking injunctive relief and treble damages. On September 4, 2020, Novartis filed, and Vetter moved to join, a motion to dismiss the complaint, to transfer the lawsuit to the Northern District of New York, or to stay the suit; and on October 19, 2020, Novartis filed, and Vetter moved to join, a second motion to dismiss the complaint on different grounds. On January 25, 2021, the Company filed an amended complaint seeking a judgment that Novartis's conduct violates Section 2 of the Sherman Antitrust Act based on additional grounds, as well as a judgment of tortious interference with contract. On February 22, 2021, Novartis filed, and Vetter moved to join, a motion to dismiss the amended complaint. On September 21, 2021, the court granted Novartis and Vetter's motion to transfer this lawsuit to the Northern District of New York. As a result, this lawsuit was transferred to the same judge that had been assigned to the patent infringement lawsuit discussed above. Proceedings Related to "Most Favored Nation" Interim Final Rule On December 11, 2020, the Company filed a lawsuit in the United States District Court for the Southern District of New York against the U.S. Department of Health and Human Services, the Secretary of HHS, the Centers for Medicare & Medicaid Services ("CMS"), and the Administrator of CMS seeking declaratory and injunctive relief related to the interim final rule with comment period entitled "Most Favored Nation (MFN) Model" issued on November 20, 2020 by HHS, acting through CMS. On the same day, the Company filed a motion for a preliminary injunction and temporary restraining order, seeking to prevent implementation of the MFN Rule. On December 22, 2020, the court heard oral argument on the Company's motion for a preliminary injunction and temporary restraining order. On December 31, 2020, the court granted the Company's motion and issued a preliminary injunction. On February 2, 2021, the government stated to the court that the Solicitor General had determined not to appeal the preliminary injunction. On February 10, 2021, the court entered a 90-day stay of the litigation and subsequently extended the stay, with the most recent 30-day extension granted on October 11, 2021. On August 6, 2021, CMS issued a Notice of Proposed Rulemaking that proposes to rescind the MFN Rule. Proceedings Relating to fasinumab On May 21, 2020, the Company and Teva Pharmaceutical Industries Limited ("Teva") filed a lawsuit against Rinat Neurosciences Corp. ("Rinat"), a wholly owned subsidiary of Pfizer Inc., in the English High Court of Justice in London, seeking invalidation and revocation of Rinat's European Patent No. 2,270,048 (the "'048 Patent"), European Patent No. 1,871,416 (the "'416 Patent"), and European Patent No. 2,305,711 (the "'711 Patent"), each of which pertains to the use of NGF monoclonal antibodies to treat certain symptoms in patients suffering from osteoarthritis. On July 21, 2020, Rinat filed its defense and counterclaim seeking a declaration of infringement of the '048 Patent by fasinumab. The counterclaim also seeks a permanent injunction, damages, an accounting of profits, and costs and interest. On December 15, 2020, Rinat filed an amended defense and counterclaim seeking a declaration of infringement of the '711 Patent by fasinumab. On May 5, 2021, the court stayed this litigation on terms mutually agreed by the parties. The '048 Patent is subject to opposition proceedings in the EPO, which were initiated by the Company on August 10, 2016 and two other opponents on August 11, 2016. On January 3, 2018, the Opposition Division of the EPO issued a preliminary, non-binding opinion regarding the validity of the '048 Patent, indicating that it considered the granted patent to be invalid. An oral hearing on the oppositions against the '048 Patent was held on November 29–30, 2018, at which the Opposition Division upheld the validity of the '048 Patent's claims in amended form. The Company filed a notice of appeal to the TBA of the EPO on March 7, 2019. On October 21, 2020, Teva filed a notice of intervention with the TBA to take part in the appeal proceedings as an intervener. An oral hearing before the TBA has been scheduled for April 5–6, 2022. The '711 Patent is also subject to opposition proceedings in the EPO, which were initiated by the Company on May 1, 2018. On January 31, 2019, the Opposition Division of the EPO issued a preliminary, non-binding opinion regarding the validity of the '711 Patent, indicating that it considered the granted patent to be invalid. An oral hearing on the opposition against the '711 Patent was held on December 3, 2019, at which the Opposition Division upheld the validity of the '711 Patent's claims in amended form. The Company filed a notice of appeal to the TBA on December 20, 2019. On January 29, 2021, Teva filed a notice of intervention with the TBA to take part in the appeal proceedings as an intervener. An oral hearing before the TBA was held on July 29, 2021, at which the '711 Patent was revoked in its entirety. Proceedings Relating to REGEN-COV (casirivimab and imdevimab) On October 5, 2020, Allele Biotechnology and Pharmaceuticals, Inc. ("Allele") filed a lawsuit (as amended on April 8, 2021) against the Company in the United States District Court for the Southern District of New York, asserting infringement of U.S. Patent No. 10,221,221 (the "'221 Patent"). Allele seeks a judgment of patent infringement of the '221 Patent, an award of monetary damages (together with interest), an order of willful infringement of the '221 Patent (which would allow the court in its discretion to award damages up to three times the amount assessed), costs and expenses of the lawsuit, and attorneys' fees. On July 16, 2021, the Company filed a motion to dismiss the complaint. Department of Justice Matters In January 2017, the Company received a subpoena from the U.S. Attorney's Office for the District of Massachusetts requesting documents relating to its support of 501(c)(3) organizations that provide financial assistance to patients; documents concerning its provision of financial assistance to patients with respect to products sold or developed by Regeneron (including EYLEA, Praluent, ARCALYST, and ZALTRAP®); and certain other related documents and communications. On June 24, 2020, the U.S. Attorney's Office for the District of Massachusetts filed a civil complaint in the U.S. District Court for the District of Massachusetts alleging violations of the federal Anti-Kickback Statute, and asserting causes of action under the federal False Claims Act and state law. On August 24, 2020, the Company filed a motion to dismiss the complaint in its entirety. On December 4, 2020, the court denied the motion to dismiss. In September 2019, the Company and Regeneron Healthcare Solutions, Inc., a wholly-owned subsidiary of the Company, each received a civil investigative demand ("CID") from the U.S. Department of Justice pursuant to the federal False Claims Act relating to remuneration paid to physicians in the form of consulting fees, advisory boards, speaker fees, and payment or reimbursement for travel and entertainment allegedly in violation of the federal Anti-Kickback Statute. The CIDs relate to EYLEA, Praluent, Dupixent, ZALTRAP, ARCALYST, and Kevzara and cover the period from January 2015 to the present. On June 3, 2021, the United States District Court for the Central District of California unsealed a qui tam complaint filed against the Company, Regeneron Healthcare Solutions, Inc., and Sanofi-Aventis U.S. LLC by two qui tam plaintiffs (known as relators) purportedly on behalf the United States and various states (the "State Plaintiffs"), asserting causes of action under the federal False Claims Act and state law. Also on June 3, 2021, the United States and the State Plaintiffs notified the court of their decision to decline to intervene in the case. On October 29, 2021, the qui tam plaintiffs filed an amended complaint in this matter. In June 2021, the Company received a CID from the U.S. Department of Justice pursuant to the federal False Claims Act. The CID states that the investigation concerns allegations that the Company (i) violated the False Claims Act by paying kickbacks to distributors and ophthalmology practices to induce purchase of EYLEA, including through discounts, rebates, credit card fees, free units of EYLEA, and inventory management systems; and (ii) inflated reimbursement rates for EYLEA by excluding applicable discounts, rebates, and benefits from the average sales price reported to CMS. The CID covers the period from January 2011 through June 2021. The Company is cooperating with this investigation. Proceedings Initiated by UnitedHealthcare On December 17, 2020, UnitedHealthcare Insurance Company and United Healthcare Services, Inc. (collectively, "UHC") filed a lawsuit against the Company in the United States District Court for the Southern District of New York alleging UHC has been damaged by the conduct alleged in the civil complaint filed by the U.S. Attorney's Office for the District of Massachusetts discussed under "Department of Justice Matters" above. UHC alleges causes of action under state law and the federal Racketeer Influenced and Corrupt Organizations Act (the "RICO Act") and seeks monetary damages and equitable relief. On March 1, 2021, the Company filed a motion to dismiss the complaint in its entirety. On March 25, 2021, UHC filed an amended complaint; and, on April 22, 2021, the Company filed a motion to dismiss this amended complaint in its entirety. Proceedings Initiated by Humana On July 22, 2021, Humana Inc. ("Humana") filed a lawsuit against the Company in the United States District Court for the Southern District of New York alleging Humana has been damaged by the conduct alleged in the civil complaint filed by the U.S. Attorney's Office for the District of Massachusetts discussed under "Department of Justice Matters" above. Humana alleges causes of action under state law and the RICO Act and seeks monetary damages and equitable relief. On September 27, 2021, the Company filed a motion to dismiss the complaint in its entirety. Shareholder Demand On or about September 30, 2020, the Company's board of directors received a demand letter from a purported shareholder of the Company. The demand alleges that Regeneron and its shareholders have been damaged by the conduct alleged in the civil complaint filed by the U.S. Attorney's Office for the District of Massachusetts discussed under "Department of Justice Matters" above. The demand letter requests that the Company's board of directors investigate alleged breaches of fiduciary duty by its officers and directors and other alleged violations of law and corporate governance practices and procedures; bring legal action against the persons responsible for causing the alleged damages; and implement and maintain an effective system of internal controls, compliance mechanisms, and corporate governance practices and procedures. The Company's board of directors, working with outside counsel, investigated and evaluated the allegations in the demand letter and has concluded that pursuing the claims alleged in the demand would not be in the Company's best interests at this time. Proceedings Relating to Shareholder Derivative Complaint On June 29, 2021, an alleged shareholder filed a shareholder derivative complaint in the New York Supreme Court, naming the current and certain former members of the Company's board of directors and certain current and former executive officers of the Company as defendants and Regeneron as a nominal defendant. The complaint asserts that the individual defendants breached their fiduciary duties in relation to the allegations in the civil complaint filed by the U.S. Attorney's Office for the District of Massachusetts discussed under "Department of Justice Matters" above. The complaint seeks an award of damages allegedly sustained by the Company; an order requiring Regeneron to take all necessary actions to reform and improve its corporate governance and internal procedures; disgorgement from the individual defendants of all profits and benefits obtained by them resulting from their sales of Regeneron stock; and costs and disbursements of the action, including attorneys' fees. On July 28, 2021, the defendants filed a notice of removal, removing the case from the New York Supreme Court to the U.S. District Court for the Southern District of New York. On September 24, 2021, the individual defendants moved to dismiss the complaint in its entirety. Also on September 24, 2021, the plaintiff filed a motion to remand the case to the New York Supreme Court.

Interim Financial Statements (Policies)	9 Months Ended
Interim Financial Statements (Policies)	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The interim Condensed Consolidated Financial Statements of Regeneron Pharmaceuticals, Inc. and its subsidiaries ("Regeneron," "Company," "we," "us," and "our") have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and disclosures necessary for a presentation of the Company's financial position, results of operations, and cash flows in conformity with accounting principles generally accepted in the United States of America. In the opinion of management, these financial statements reflect all normal recurring adjustments and accruals necessary for a fair statement of the Company's condensed consolidated financial statements for such periods. The results of operations for any interim period are not necessarily indicative of the results for the full year. The December 31, 2020 Condensed Consolidated Balance Sheet data were derived from audited financial statements, but do not include all disclosures required by accounting principles generally accepted in the United States of America. These financial statements should be read in conjunction with the financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020.
Legal Matters	Costs associated with the Company's involvement in legal proceedings are expensed as incurred.

Product Sales (Tables)

9 Months Ended

Sep. 30, 2021

Schedule of product sales

Net product sales consist of the following:


(In millions)	Three Months Ended September 30,					Nine Months Ended September 30,
Net Product Sales in the United States	2021			2020		2021			2020
EYLEA®	$	1,473.4		$	1,318.3	$	4,245.1		$	3,604.0
Libtayo®	78.4			71.6		225.5			196.6
Praluent®	44.8			48.5		130.0			95.7		*
REGEN-COV®	676.7			40.2		3,530.1			40.2
Evkeeza®	6.6			—		9.1			—
ARCALYST®	—		**	3.6		2.2		**	9.3
	$	2,279.9		$	1,482.2	$	8,142.0		$	3,945.8

* Effective April 1, 2020, the Company became solely responsible for the development and commercialization of Praluent in the United States and records net product sales of Praluent in the United States. Previously, Sanofi recorded net product sales of Praluent in the United States. See Note 3 for further details.
** Effective April 1, 2021, Kiniksa records net product sales of ARCALYST in the United States. Previously, the Company recorded net product sales of ARCALYST in the United States.

Amounts recognized in our Statements of Operations in connection with our collaborations with Sanofi are detailed below:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Antibody:
Regeneron's share of profits in connection with commercialization of antibodies	Collaboration revenue	$	387.0	$	212.8	$	975.2	$	555.6
Sales-based milestone earned	Collaboration revenue	$	50.0	$	50.0	$	50.0	$	50.0
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	144.7	$	94.3	$	361.2	$	275.0
Reimbursement of research and development expenses	Reduction of Research and development expense	$	45.2	$	45.5	$	122.3	$	174.4
Regeneron's obligation for its share of Sanofi research and development expenses	Research and development expense	$	(10.3)	$	(17.5)	$	(32.8)	$	(59.1)
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	79.0	$	83.2	$	216.9	$	260.4

Immuno-oncology:
Regeneron's share of losses in connection with commercialization of Libtayo outside the United States	Collaboration revenue	$	(3.0)	$	(4.7)	$	(12.6)	$	(17.3)
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	3.1	$	0.9	$	10.5	$	6.0
Reimbursement of research and development expenses	Reduction of Research and development expense	$	21.8	$	49.8	$	66.2	$	136.7
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	22.8	$	14.5	$	62.0	$	39.2
Regeneron's obligation for its share of Sanofi commercial expenses	Selling, general, and administrative expense	$	(9.4)	$	(6.1)	$	(28.0)	$	(15.0)
Regeneron's obligation for Sanofi's share of Libtayo U.S. gross profits	Cost of goods sold	$	(34.6)	$	(31.5)	$	(99.4)	$	(86.5)
Amounts recognized in connection with up-front payments received	Other operating income	$	(47.7)	$	20.0	$	(4.1)	$	57.0

Amounts recognized in our Statements of Operations in connection with our Bayer EYLEA collaboration are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	Collaboration revenue	$	351.0	$	287.9	$	995.3	$	772.6
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	14.0	$	12.0	$	41.6	$	52.9
Reimbursement of research and development expenses	Reduction of Research and development expense	$	14.5	$	11.5	$	35.2	$	34.3
Regeneron's obligation for its share of Bayer research and development expenses	Research and development expense	$	(8.0)	$	(12.9)	$	(31.4)	$	(26.3)

Amounts recognized in our Statements of Operations in connection with our collaboration with Teva are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Reimbursement of research and development expenses	Reduction of Research and development expense	$	5.1	$	25.9	$	36.6	$	82.1
Amounts recognized in connection with up-front and development milestone payments received	Other operating income	$	3.2	$	17.2	$	22.6	$	54.5

Amounts recognized in our Statements of Operations in connection with the Roche Collaboration Agreement are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Global gross profit true-up payment owed from Roche in connection with sales of casirivimab and imdevimab	Collaboration revenue	$	127.1	—		$	361.8	—
Reimbursement of research and development expenses	Reduction of Research and development expense	$	10.5	$	9.5	$	138.3	$	9.5

Schedules of sales to customers as percentage of total gross product revenue

Sales to each of these customers as a percentage of the Company's total gross product revenue are as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Besse Medical, a subsidiary of AmerisourceBergen Corporation	40	%	50	%	33	%	52	%
McKesson Corporation	24	%	34	%	20	%	34	%
U.S. Government (see Note 3)	25	%	*		38	%	*

* Sales to the U.S. Government represented less than 10% of total gross product revenue during the period.

Collaboration, License, and Other Agreements (Tables)

9 Months Ended

Sep. 30, 2021

Schedule of collaborative revenue

Net product sales consist of the following:


(In millions)	Three Months Ended September 30,					Nine Months Ended September 30,
Net Product Sales in the United States	2021			2020		2021			2020
EYLEA®	$	1,473.4		$	1,318.3	$	4,245.1		$	3,604.0
Libtayo®	78.4			71.6		225.5			196.6
Praluent®	44.8			48.5		130.0			95.7		*
REGEN-COV®	676.7			40.2		3,530.1			40.2
Evkeeza®	6.6			—		9.1			—
ARCALYST®	—		**	3.6		2.2		**	9.3
	$	2,279.9		$	1,482.2	$	8,142.0		$	3,945.8

* Effective April 1, 2020, the Company became solely responsible for the development and commercialization of Praluent in the United States and records net product sales of Praluent in the United States. Previously, Sanofi recorded net product sales of Praluent in the United States. See Note 3 for further details.
** Effective April 1, 2021, Kiniksa records net product sales of ARCALYST in the United States. Previously, the Company recorded net product sales of ARCALYST in the United States.

Amounts recognized in our Statements of Operations in connection with our collaborations with Sanofi are detailed below:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Antibody:
Regeneron's share of profits in connection with commercialization of antibodies	Collaboration revenue	$	387.0	$	212.8	$	975.2	$	555.6
Sales-based milestone earned	Collaboration revenue	$	50.0	$	50.0	$	50.0	$	50.0
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	144.7	$	94.3	$	361.2	$	275.0
Reimbursement of research and development expenses	Reduction of Research and development expense	$	45.2	$	45.5	$	122.3	$	174.4
Regeneron's obligation for its share of Sanofi research and development expenses	Research and development expense	$	(10.3)	$	(17.5)	$	(32.8)	$	(59.1)
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	79.0	$	83.2	$	216.9	$	260.4

Immuno-oncology:
Regeneron's share of losses in connection with commercialization of Libtayo outside the United States	Collaboration revenue	$	(3.0)	$	(4.7)	$	(12.6)	$	(17.3)
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	3.1	$	0.9	$	10.5	$	6.0
Reimbursement of research and development expenses	Reduction of Research and development expense	$	21.8	$	49.8	$	66.2	$	136.7
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	22.8	$	14.5	$	62.0	$	39.2
Regeneron's obligation for its share of Sanofi commercial expenses	Selling, general, and administrative expense	$	(9.4)	$	(6.1)	$	(28.0)	$	(15.0)
Regeneron's obligation for Sanofi's share of Libtayo U.S. gross profits	Cost of goods sold	$	(34.6)	$	(31.5)	$	(99.4)	$	(86.5)
Amounts recognized in connection with up-front payments received	Other operating income	$	(47.7)	$	20.0	$	(4.1)	$	57.0

Amounts recognized in our Statements of Operations in connection with our Bayer EYLEA collaboration are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	Collaboration revenue	$	351.0	$	287.9	$	995.3	$	772.6
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	14.0	$	12.0	$	41.6	$	52.9
Reimbursement of research and development expenses	Reduction of Research and development expense	$	14.5	$	11.5	$	35.2	$	34.3
Regeneron's obligation for its share of Bayer research and development expenses	Research and development expense	$	(8.0)	$	(12.9)	$	(31.4)	$	(26.3)

Amounts recognized in our Statements of Operations in connection with our collaboration with Teva are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Reimbursement of research and development expenses	Reduction of Research and development expense	$	5.1	$	25.9	$	36.6	$	82.1
Amounts recognized in connection with up-front and development milestone payments received	Other operating income	$	3.2	$	17.2	$	22.6	$	54.5

Amounts recognized in our Statements of Operations in connection with the Roche Collaboration Agreement are as follows:


	Statement of Operations Classification	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)		2021		2020		2021		2020
Global gross profit true-up payment owed from Roche in connection with sales of casirivimab and imdevimab	Collaboration revenue	$	127.1	—		$	361.8	—
Reimbursement of research and development expenses	Reduction of Research and development expense	$	10.5	$	9.5	$	138.3	$	9.5

Schedule of accounts receivable and deferred revenue information

The following table summarizes contract balances in connection with the Company's Antibody Collaboration with Sanofi:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	536.0	$	407.7
Deferred revenue	$	431.7	$	347.7

The following table summarizes contract balances in connection with the Company's IO Collaboration with Sanofi:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	0.1	$	(6.5)
Deferred revenue	$	16.2	$	10.7
Other liabilities	$	286.0	$	280.9

The following table summarizes contract balances in connection with our Bayer EYLEA collaboration:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	374.8	$	336.2
Deferred revenue	$	115.2	$	99.7

The following table summarizes contract balances in connection with the Teva Collaboration Agreement:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	5.2	$	27.7
Other liabilities	$	43.3	$	66.8

The following table summarizes contract balances in connection with the Roche Collaboration Agreement:


	September 30,		December 31,
(In millions)	2021		2020
Accounts receivable, net	$	305.5	$	77.1

Net Income Per Share (Tables)

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Basic and Diluted Net Income (Loss) Per Share

The calculations of basic and diluted net income per share are as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions, except per share data)	2021		2020		2021		2020
Net income - basic and diluted	$	1,632.2	$	842.1	$	5,846.3	$	2,364.0

Weighted average shares - basic	106.2		105.5		105.5		108.3
Effect of dilutive securities:
Stock options	6.4		7.8		5.3		7.3
Restricted stock awards and restricted stock units	1.3		0.6		1.0		0.5
Weighted average shares - diluted	113.9		113.9		111.8		116.1

Net income per share - basic	$	15.37	$	7.98	$	55.42	$	21.83
Net income per share - diluted	$	14.33	$	7.39	$	52.29	$	20.36

Antidilutive Securities

Shares which have been excluded from diluted per share amounts because their effect would have been antidilutive include the following:


	Three Months Ended September 30,		Nine Months Ended September 30,
(Shares in millions)	2021	2020	2021	2020
Stock options	0.4	0.1	4.8	2.6

Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2021

Investments, Debt and Equity Securities [Abstract]

Available-for-sale Debt Securities

The following tables summarize the Company's investments in available-for-sale debt securities:


(In millions)	Amortized		Unrealized				Fair
As of September 30, 2021	Cost Basis		Gains		Losses		Value
Corporate bonds	$	5,911.8	$	19.9	$	(6.9)	$	5,924.8
U.S. government and government agency obligations	101.2		0.6		(0.1)		101.7
Sovereign bonds	64.6		0.5		—		65.1
Commercial paper	272.6		—		—		272.6
Certificates of deposit	231.7		—		—		231.7
Asset-backed securities	19.0		—		—		19.0
	$	6,600.9	$	21.0	$	(7.0)	$	6,614.9

As of December 31, 2020
Corporate bonds	$	3,053.0	$	37.5	$	(0.2)	$	3,090.3
U.S. government and government agency obligations	127.6		1.3		—		128.9
Sovereign bonds	65.2		1.1		—		66.3
Commercial paper	276.0		0.1		—		276.1
Certificates of deposit	127.4		0.1		—		127.5
	$	3,649.2	$	40.1	$	(0.2)	$	3,689.1

Marketable Securities, Based on Contractual Maturity Dates

The fair values of available-for-sale debt securities by contractual maturity consist of the following:


	September 30,		December 31,
(In millions)	2021		2020
Maturities within one year	$	2,355.2	$	1,393.3
Maturities after one year through five years	4,259.7		2,295.8
	$	6,614.9	$	3,689.1

Fair Value and Unrealized Losses of Marketable Securities


	Less than 12 Months				12 Months or Greater		Total
(In millions) As of September 30, 2021	Fair Value		Unrealized Loss		Fair Value	Unrealized Loss	Fair Value		Unrealized Loss
Corporate bonds	$	2,905.9	$	(6.9)	—	—	$	2,905.9	$	(6.9)
U.S. government and government agency obligations	27.0		(0.1)		—	—	27.0		(0.1)
	$	2,932.9	$	(7.0)	—	—	$	2,932.9	$	(7.0)

As of December 31, 2020
Corporate bonds	$	364.5	$	(0.2)	—	—	$	364.5	$	(0.2)

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Schedule of assets measured at fair value on a recurring basis

•Level 1 - Quoted prices in active markets for identical assets

•Level 3 - Significant other unobservable inputs


(In millions)			Fair Value Measurements at Reporting Date
As of September 30, 2021	Fair Value		Level 1		Level 2
Available-for-sale debt securities:
Corporate bonds	$	5,924.8	—		$	5,924.8
U.S. government and government agency obligations	101.7		—		101.7
Sovereign bonds	65.1		—		65.1
Commercial paper	272.6		—		272.6
Certificates of deposit	231.7		—		231.7
Asset-backed securities	19.0		—		19.0
Equity securities (unrestricted)	35.7		$	35.7	—
Equity securities (restricted)	1,335.9		1,335.9		—
	$	7,986.5	$	1,371.6	$	6,614.9

As of December 31, 2020
Available-for-sale debt securities:
Corporate bonds	$	3,090.3	—		$	3,090.3
U.S. government and government agency obligations	128.9		—		128.9
Sovereign bonds	66.3		—		66.3
Commercial paper	276.1		—		276.1
Certificates of deposit	127.5		—		127.5
Equity securities (unrestricted)	48.3		$	48.3	—
Equity securities (restricted)	791.5		791.5		—
	$	4,528.9	$	839.8	$	3,689.1

Inventories (Tables)

9 Months Ended

Sep. 30, 2021

Inventory Disclosure [Abstract]

Schedule of Inventory, Current

Inventories consist of the following:


	September 30,		December 31,
(In millions)	2021		2020
Raw materials	$	646.3	$	459.4
Work-in-process	843.7		904.6
Finished goods	60.1		121.7
Deferred costs	503.7		430.9
	$	2,053.8	$	1,916.6

Debt (Tables)

9 Months Ended

Sep. 30, 2021

Debt Disclosure [Abstract]

Summary of Issued Senior Unsecured Notes

Long-term debt in connection with our senior unsecured notes (collectively, the "Notes"), net of underwriting discounts and offering expenses, consists of the following:


	September 30,		December 31,
(In millions)	2021		2020
1.750% Senior Notes due September 2030	$	1,239.6	$	1,238.7
2.800% Senior Notes due September 2050	740.0		739.8
	$	1,979.6	$	1,978.5

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2021

Equity [Abstract]

Schedule of Shares Repurchased


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2021		2020		2021		2020
Number of shares repurchased	0.3		0.2		1.6		0.9
Total cost of shares received	$	190.5	$	100.4	$	802.7	$	373.3

Statement of Cash Flows (Tables)

9 Months Ended

Sep. 30, 2021

Cash and Cash Equivalents [Abstract]

Schedule of Cash and Cash Equivalents


	September 30,
(In millions)	2021		2020
Cash and cash equivalents	$	3,432.4	$	1,573.0
Restricted cash included in Other noncurrent assets	12.5		13.6
Total cash, cash equivalents, and restricted cash shown in the Condensed Consolidated Statement of Cash Flows	$	3,444.9	$	1,586.6

Restrictions on Cash and Cash Equivalents


	September 30,
(In millions)	2021		2020
Cash and cash equivalents	$	3,432.4	$	1,573.0
Restricted cash included in Other noncurrent assets	12.5		13.6
Total cash, cash equivalents, and restricted cash shown in the Condensed Consolidated Statement of Cash Flows	$	3,444.9	$	1,586.6

Summary of Non-Cash Investing and Financing Activities

The following amounts were included in accounts payable, accrued expenses, and other liabilities:


	September 30,		December 31,		September 30,		December 31,
(In millions)	2021		2020		2020		2019
Accrued capital expenditures	$	70.1	$	83.6	$	100.4	$	133.7

Product Sales - Schedule of Net Product Sales (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 3,452.8	$ 2,294.0	$ 11,120.0	$ 6,074.2
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenues	2,279.9	1,482.2	8,142.0	3,945.8
UNITED STATES \| EYLEA
Disaggregation of Revenue [Line Items]
Revenues	1,473.4	1,318.3	4,245.1	3,604.0
UNITED STATES \| Libtayo
Disaggregation of Revenue [Line Items]
Revenues	78.4	71.6	225.5	196.6
UNITED STATES \| Praluent
Disaggregation of Revenue [Line Items]
Revenues	44.8	48.5	130.0	95.7
UNITED STATES \| REGEN-COV
Disaggregation of Revenue [Line Items]
Revenues	676.7	40.2	3,530.1	40.2
UNITED STATES \| Evkeeza
Disaggregation of Revenue [Line Items]
Revenues	6.6	0.0	9.1	0.0
UNITED STATES \| ARCALYST
Disaggregation of Revenue [Line Items]
Revenues	$ 0.0	$ 3.6	$ 2.2	$ 9.3

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9031-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9038-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130543-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9054-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130545-203045

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

Product Sales - Schedule of Concentration of Risk, by Risk Factor (Details) - Gross product revenue - Customer concentration risk	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Besse Medical, a subsidiary of AmerisourceBergen Corporation
Concentration Risk [Line Items]
Concentration risk, percentage	40.00%	50.00%	33.00%	52.00%
McKesson Corporation
Concentration Risk [Line Items]
Concentration risk, percentage	24.00%	34.00%	20.00%	34.00%
U.S. Government
Concentration Risk [Line Items]
Concentration risk, percentage	25.00%		38.00%

Product Sales - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	$ 5,452.0	$ 4,114.7
Trade accounts receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	$ 4,086.0	$ 3,112.0

Collaboration, License, and Other Agreements - Amounts Recognized In Statement of Operations with Sanofi (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 3,452.8	$ 2,294.0	$ 11,120.0	$ 6,074.2
Sanofi Collaboration Agreement, Antibody \| Collaboration revenue \| Regeneron's share of profits (losses) in connection with commercialization
Disaggregation of Revenue [Line Items]
Revenues	387.0	212.8	975.2	555.6
Sanofi Collaboration Agreement, Antibody \| Collaboration revenue \| Sales-based milestone earned
Disaggregation of Revenue [Line Items]
Revenues	50.0	50.0	50.0	50.0
Sanofi Collaboration Agreement, Antibody \| Collaboration revenue \| Reimbursement for manufacturing of commercial supplies
Disaggregation of Revenue [Line Items]
Revenues	144.7	94.3	361.2	275.0
Sanofi Collaboration Agreement, Antibody \| Research and development expense \| Reimbursement of research and development expenses
Disaggregation of Revenue [Line Items]
Revenues	45.2	45.5	122.3	174.4
Sanofi Collaboration Agreement, Antibody \| Research and development expense \| Regeneron's obligation for its share of Sanofi research and development expenses
Disaggregation of Revenue [Line Items]
Revenues	(10.3)	(17.5)	(32.8)	(59.1)
Sanofi Collaboration Agreement, Antibody \| Selling, general and administrative expense \| Reimbursement of commercialization-related expenses
Disaggregation of Revenue [Line Items]
Revenues	79.0	83.2	216.9	260.4
Sanofi Collaboration Agreement, Immuno-oncology \| Collaboration revenue \| Regeneron's share of profits (losses) in connection with commercialization \| Outside United States
Disaggregation of Revenue [Line Items]
Revenues	(3.0)	(4.7)	(12.6)	(17.3)
Sanofi Collaboration Agreement, Immuno-oncology \| Collaboration revenue \| Reimbursement for manufacturing of commercial supplies
Disaggregation of Revenue [Line Items]
Revenues	3.1	0.9	10.5	6.0
Sanofi Collaboration Agreement, Immuno-oncology \| Research and development expense \| Reimbursement of research and development expenses
Disaggregation of Revenue [Line Items]
Revenues	21.8	49.8	66.2	136.7
Sanofi Collaboration Agreement, Immuno-oncology \| Selling, general and administrative expense \| Reimbursement of commercialization-related expenses
Disaggregation of Revenue [Line Items]
Revenues	22.8	14.5	62.0	39.2
Sanofi Collaboration Agreement, Immuno-oncology \| Selling, general and administrative expense \| Regeneron's obligation for its share of Sanofi commercial expenses
Disaggregation of Revenue [Line Items]
Revenues	(9.4)	(6.1)	(28.0)	(15.0)
Sanofi Collaboration Agreement, Immuno-oncology \| Cost of goods sold \| Regeneron's obligation for Sanofi's share of Libtayo U.S. gross profits
Disaggregation of Revenue [Line Items]
Revenues	(34.6)	(31.5)	(99.4)	(86.5)
Sanofi Collaboration Agreement, Immuno-oncology \| Other operating income \| Amounts recognized in connection with up-front payments received
Disaggregation of Revenue [Line Items]
Revenues	$ (47.7)	$ 20.0	$ (4.1)	$ 57.0

Collaboration, License, and Other Agreements - Sanofi, Antibody Narrative (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Apr. 01, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues		$ 3,452.8	$ 2,294.0	$ 11,120.0	$ 6,074.2
Sanofi Collaboration Agreement, Antibody
Disaggregation of Revenue [Line Items]
Levels of twelve-month sales at which sales milestone payments would be received				$ 1,500.0	$ 1,000.0
Period for achieving sales target for milestone payment, rolling basis				12 months	12 months
Remaining amount of sales milestone payments if total sales achieve specific levels				$ 150.0
Sanofi Collaboration Agreement, Antibody \| First Sales Milestone
Disaggregation of Revenue [Line Items]
Revenues			$ 50.0
Sanofi Collaboration Agreement, Antibody \| Second Sales Milestone
Disaggregation of Revenue [Line Items]
Revenues		$ 50.0
Sanofi Collaboration Agreement, Antibody \| Minimum
Disaggregation of Revenue [Line Items]
Percentage of trial costs required to be funded by collaborating party				80.00%
Sanofi Collaboration Agreement, Antibody \| Maximum
Disaggregation of Revenue [Line Items]
Percentage of trial costs required to be funded by collaborating party				100.00%
Praluent Agreement
Disaggregation of Revenue [Line Items]
Royalty percentage to be received on net product sales outside of the United States	5.00%
Percentage of damages company is responsible for	50.00%
Praluent Agreement \| Sanofi
Disaggregation of Revenue [Line Items]
Percentage of royalty payment that can be used to offset litigation proceedings (up to)	50.00%

Collaboration, License, and Other Agreements - Schedule of Contract Balances, Antibody Collaboration (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ 5,452.0	$ 4,114.7
Sanofi Collaboration Agreement, Antibody
Disaggregation of Revenue [Line Items]
Accounts receivable, net	536.0	407.7
Deferred revenue	$ 431.7	$ 347.7

Collaboration, License, and Other Agreements - Schedule of Contract Balances, IO Collaboration (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ 5,452.0	$ 4,114.7
Sanofi Collaboration Agreement, Immuno-oncology
Disaggregation of Revenue [Line Items]
Accounts receivable, net	0.1	6.5
Deferred revenue	16.2	10.7
Other liabilities	$ 286.0	$ 280.9

Collaboration, License, and Other Agreements - Sanofi, Immuno-Oncology Narrative (Details) - Sanofi Collaboration Agreement, Immuno-oncology $ in Millions	3 Months Ended
	Sep. 30, 2021 USD ($)
Disaggregation of Revenue [Line Items]
Cumulative catch-up adjustment to revenue, change in estimate of transaction price	$ 66.9
Remaining performance obligation	$ 591.4

Collaboration, License, and Other Agreements - Bayer Narrative (Details) - Bayer	9 Months Ended
	Sep. 30, 2021
Minimum
Disaggregation of Revenue [Line Items]
Revenue based on percentage of annual sales in Japan	33.50%
Maximum
Disaggregation of Revenue [Line Items]
Revenue based on percentage of annual sales in Japan	40.00%

Collaboration Agreements - Amounts Recognized in Statement of Operations with Bayer (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 3,452.8	$ 2,294.0	$ 11,120.0	$ 6,074.2
Bayer \| Outside United States \| Collaboration revenue \| Regeneron's net profit in connection with commercialization of EYLEA outside the United States
Disaggregation of Revenue [Line Items]
Revenues	351.0	287.9	995.3	772.6
Bayer \| Outside United States \| Collaboration revenue \| Reimbursement for manufacturing of commercial supplies
Disaggregation of Revenue [Line Items]
Revenues	14.0	12.0	41.6	52.9
Bayer \| Outside United States \| Research and development expense \| Reimbursement of research and development expenses
Disaggregation of Revenue [Line Items]
Revenues	14.5	11.5	35.2	34.3
Bayer \| Outside United States \| Research and development expense \| Regeneron's obligation for its share of Bayer research and development expenses
Disaggregation of Revenue [Line Items]
Revenues	$ (8.0)	$ (12.9)	$ (31.4)	$ (26.3)

Collaboration, License, and Other Agreements - Schedule of Contract Balances, Bayer Collaboration (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ 5,452.0	$ 4,114.7
Bayer
Disaggregation of Revenue [Line Items]
Accounts receivable, net	374.8	336.2
Deferred revenue	$ 115.2	$ 99.7

Collaboration, License, and Other Agreements - Amounts Recognized in Statement of Operations with Teva (Details) - Teva - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reimbursement of research and development expenses \| Research and development expense
Disaggregation of Revenue [Line Items]
Reduction of Research and development expense	$ 5.1	$ 25.9	$ 36.6	$ 82.1
Amounts recognized in connection with up-front and development milestone payments received \| Other operating income
Disaggregation of Revenue [Line Items]
Other operating income	$ 3.2	$ 17.2	$ 22.6	$ 54.5

Collaboration, License, and Other Agreements - Schedule of Contract Balances, Teva Collaboration (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ 5,452.0	$ 4,114.7
Teva
Disaggregation of Revenue [Line Items]
Accounts receivable, net	5.2	27.7
Other liabilities	$ 43.3	$ 66.8

Collaboration, License, and Other Agreements - Teva Narrative (Details) $ in Millions	Sep. 30, 2021 USD ($)
Teva
Disaggregation of Revenue [Line Items]
Remaining performance obligation	$ 96.7

Collaboration, License, and Other Agreements - U.S. Government Narrative (Details) - REGEN-COV - U.S. Government - Other Transaction Agreement $ in Millions		1 Months Ended	6 Months Ended
	Jan. 31, 2022 USD ($)	Sep. 30, 2021 dose	Jun. 30, 2021 dose
Disaggregation of Revenue [Line Items]
Number of doses \| dose		1,400,000	1,250,000
Scenario, Forecast
Disaggregation of Revenue [Line Items]
Maximum agreement payments \| $	$ 2,940

Collaboration, License, and Other Agreements - Amounts Recognized in Statement of Operations with Roche (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 3,452.8	$ 2,294.0	$ 11,120.0	$ 6,074.2
Casirivimab and imdevimab \| Roche Collaboration Agreement \| Collaboration revenue
Disaggregation of Revenue [Line Items]
Revenues	127.1	0.0	361.8	0.0
Casirivimab and imdevimab \| Roche Collaboration Agreement \| Research and development expense
Disaggregation of Revenue [Line Items]
Reduction of Research and development expense	$ 10.5	$ 9.5	$ 138.3	$ 9.5

Collaboration, License, and Other Agreements - Schedule of Contract Balances, Roche Collaboration (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ 5,452.0	$ 4,114.7
Roche Collaboration Agreement
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ 305.5	$ 77.1

Collaboration, License, and Other Agreements - Intellia Narrative (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	May 31, 2020
Research Collaboration and Licensing Arrangements [Line Items]
Research and development	$ 665.4	$ 684.6		$ 2,122.5	$ 1,990.5
Intellia
Research Collaboration and Licensing Arrangements [Line Items]
Upfront payment made for collaboration agreement			$ 70.0
Research and development			$ 15.0
Intellia \| Common Stock
Research Collaboration and Licensing Arrangements [Line Items]
Shares purchase price						$ 30.0

Net Income Per Share - Schedule of Basic and Diluted Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net income - basic and diluted	$ 1,632.2	$ 3,098.9	$ 1,115.2	$ 842.1	$ 897.3	$ 624.6	$ 5,846.3	$ 2,364.0
Weighted average shares - basic (in shares)	106.2			105.5			105.5	108.3
Weighted average shares - diluted (in shares)	113.9			113.9			111.8	116.1
Net income per share - basic (in dollars per share)	$ 15.37			$ 7.98			$ 55.42	$ 21.83
Net income per share - diluted (in dollars per share)	$ 14.33			$ 7.39			$ 52.29	$ 20.36
Stock options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	6.4			7.8			5.3	7.3
Restricted stock awards and restricted stock units
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	1.3			0.6			1.0	0.5

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (e)(4)
-URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=125511455&loc=d3e1448-109256

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=125511455&loc=d3e1337-109256

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=125512782&loc=d3e4984-109258

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(23))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=125512782&loc=d3e3842-109258

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22644-107794

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(25))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=125511455&loc=d3e1252-109256

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125511455&loc=SL5780133-109256

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(27))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=125512782&loc=d3e4984-109258

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22644-107794

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=125512782&loc=d3e3842-109258

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=125511455&loc=d3e1252-109256

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125511455&loc=SL5780133-109256

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(27))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(23))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=125511455&loc=d3e1337-109256

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (e)(4)
-URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(25))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=124431353&loc=SL124452729-227067

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iii)(A))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(i))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(i))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22663-107794

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 17: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(ii))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=125511455&loc=SL5780133-109256

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22658-107794

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669619-108580

Reference 25: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8924-108599

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669625-108580

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(5))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756

Reference 32: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(A))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 34: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

Reference 35: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Net Income Per Share - Schedule of Antidilutive Securities Excluded From Computation (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive weighted average number of shares (in shares)	0.4	0.1	4.8	2.6

Marketable Securities - Schedule of Investments in Available For Sale Debt Securities (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 6,600.9	$ 3,649.2
Unrealized Gains	21.0	40.1
Unrealized Losses	(7.0)	(0.2)
Fair Value	6,614.9	3,689.1
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	5,911.8	3,053.0
Unrealized Gains	19.9	37.5
Unrealized Losses	(6.9)	(0.2)
Fair Value	5,924.8	3,090.3
U.S. government and government agency obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	101.2	127.6
Unrealized Gains	0.6	1.3
Unrealized Losses	(0.1)	0.0
Fair Value	101.7	128.9
Sovereign bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	64.6	65.2
Unrealized Gains	0.5	1.1
Unrealized Losses	0.0	0.0
Fair Value	65.1	66.3
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	272.6	276.0
Unrealized Gains	0.0	0.1
Unrealized Losses	0.0	0.0
Fair Value	272.6	276.1
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	231.7	127.4
Unrealized Gains	0.0	0.1
Unrealized Losses	0.0	0.0
Fair Value	231.7	$ 127.5
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	19.0
Unrealized Gains	0.0
Unrealized Losses	0.0
Fair Value	$ 19.0

Marketable Securities - Schedule of Debt Securities Based on Contractual Maturity Dates (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Maturities within one year	$ 2,355.2	$ 1,393.3
Maturities after one year through five years	4,259.7	2,295.8
Total	$ 6,614.9	$ 3,689.1

Marketable Securities - Schedule of Fair Value and Unrealized Losses of Debt Securities (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	$ 2,932.9
Unrealized Loss - Less than 12 months	(7.0)
Fair Value - 12 Months or Greater	0.0
Unrealized Loss - 12 Months or Greater	0.0
Fair Value - Total	2,932.9
Unrealized Loss - Total	(7.0)
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	2,905.9	$ 364.5
Unrealized Loss - Less than 12 months	(6.9)	(0.2)
Fair Value - 12 Months or Greater	0.0	0.0
Unrealized Loss - 12 Months or Greater	0.0	0.0
Fair Value - Total	2,905.9	364.5
Unrealized Loss - Total	(6.9)	$ (0.2)
U.S. government and government agency obligations
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	27.0
Unrealized Loss - Less than 12 months	(0.1)
Fair Value - 12 Months or Greater	0.0
Unrealized Loss - 12 Months or Greater	0.0
Fair Value - Total	27.0
Unrealized Loss - Total	$ (0.1)

Marketable Securities - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Marketable securities, realized gain (loss)	$ 0.0	$ 0.0	$ 0.0
Marketable securities, realized gain				$ 28.5
Marketable securities, realized loss				$ 0.0

Fair Value Measurements - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Available-for-sale debt securities:
Available-for-sale debt securities	$ 6,614.9	$ 3,689.1
Corporate bonds
Available-for-sale debt securities:
Available-for-sale debt securities	5,924.8	3,090.3
U.S. government and government agency obligations
Available-for-sale debt securities:
Available-for-sale debt securities	101.7	128.9
Sovereign bonds
Available-for-sale debt securities:
Available-for-sale debt securities	65.1	66.3
Commercial paper
Available-for-sale debt securities:
Available-for-sale debt securities	272.6	276.1
Certificates of deposit
Available-for-sale debt securities:
Available-for-sale debt securities	231.7	127.5
Asset-backed securities
Available-for-sale debt securities:
Available-for-sale debt securities	19.0
Measured on a recurring basis
Available-for-sale debt securities:
Total marketable securities	7,986.5	4,528.9
Measured on a recurring basis \| Unrestricted
Available-for-sale debt securities:
Equity securities	35.7	48.3
Measured on a recurring basis \| Restricted
Available-for-sale debt securities:
Equity securities	1,335.9	791.5
Measured on a recurring basis \| Corporate bonds
Available-for-sale debt securities:
Available-for-sale debt securities	5,924.8	3,090.3
Measured on a recurring basis \| U.S. government and government agency obligations
Available-for-sale debt securities:
Available-for-sale debt securities	101.7	128.9
Measured on a recurring basis \| Sovereign bonds
Available-for-sale debt securities:
Available-for-sale debt securities	65.1	66.3
Measured on a recurring basis \| Commercial paper
Available-for-sale debt securities:
Available-for-sale debt securities	272.6	276.1
Measured on a recurring basis \| Certificates of deposit
Available-for-sale debt securities:
Available-for-sale debt securities	231.7	127.5
Measured on a recurring basis \| Asset-backed securities
Available-for-sale debt securities:
Available-for-sale debt securities	19.0
Measured on a recurring basis \| Level 1
Available-for-sale debt securities:
Total marketable securities	1,371.6	839.8
Measured on a recurring basis \| Level 1 \| Unrestricted
Available-for-sale debt securities:
Equity securities	35.7	48.3
Measured on a recurring basis \| Level 1 \| Restricted
Available-for-sale debt securities:
Equity securities	1,335.9	791.5
Measured on a recurring basis \| Level 1 \| Corporate bonds
Available-for-sale debt securities:
Available-for-sale debt securities	0.0	0.0
Measured on a recurring basis \| Level 1 \| U.S. government and government agency obligations
Available-for-sale debt securities:
Available-for-sale debt securities	0.0	0.0
Measured on a recurring basis \| Level 1 \| Sovereign bonds
Available-for-sale debt securities:
Available-for-sale debt securities	0.0	0.0
Measured on a recurring basis \| Level 1 \| Commercial paper
Available-for-sale debt securities:
Available-for-sale debt securities	0.0	0.0
Measured on a recurring basis \| Level 1 \| Certificates of deposit
Available-for-sale debt securities:
Available-for-sale debt securities	0.0	0.0
Measured on a recurring basis \| Level 1 \| Asset-backed securities
Available-for-sale debt securities:
Available-for-sale debt securities	0.0
Measured on a recurring basis \| Level 2
Available-for-sale debt securities:
Total marketable securities	6,614.9	3,689.1
Measured on a recurring basis \| Level 2 \| Unrestricted
Available-for-sale debt securities:
Equity securities	0.0	0.0
Measured on a recurring basis \| Level 2 \| Restricted
Available-for-sale debt securities:
Equity securities	0.0	0.0
Measured on a recurring basis \| Level 2 \| Corporate bonds
Available-for-sale debt securities:
Available-for-sale debt securities	5,924.8	3,090.3
Measured on a recurring basis \| Level 2 \| U.S. government and government agency obligations
Available-for-sale debt securities:
Available-for-sale debt securities	101.7	128.9
Measured on a recurring basis \| Level 2 \| Sovereign bonds
Available-for-sale debt securities:
Available-for-sale debt securities	65.1	66.3
Measured on a recurring basis \| Level 2 \| Commercial paper
Available-for-sale debt securities:
Available-for-sale debt securities	272.6	276.1
Measured on a recurring basis \| Level 2 \| Certificates of deposit
Available-for-sale debt securities:
Available-for-sale debt securities	231.7	$ 127.5
Measured on a recurring basis \| Level 2 \| Asset-backed securities
Available-for-sale debt securities:
Available-for-sale debt securities	$ 19.0

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Net unrealized gain (loss) on securities	$ (29.1)	$ (37.5)	$ 523.8	$ 133.8
Securities owned not readily marketable	40.0		40.0		$ 59.2
Long-term debt fair value	$ 1,891.0		$ 1,891.0		$ 1,958.0

Inventories - Schedule of Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 646.3	$ 459.4
Work-in-process	843.7	904.6
Finished goods	60.1	121.7
Deferred costs	503.7	430.9
Total Inventories	$ 2,053.8	$ 1,916.6

Inventories - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Inventories - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Inventory Disclosure [Abstract]
Inventory write-offs and reserves	$ 38.7	$ 11.8	$ 188.0	$ 23.6

Debt - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Debt - Narrative (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2021	Aug. 31, 2020	May 31, 2020
Senior Unsecured Notes
Line of Credit Facility [Line Items]
Interest expense	$ 11,100,000	$ 33,300,000
Bridge Facility \| Bridge Facility
Line of Credit Facility [Line Items]
Debt, principal amount				$ 1,500,000,000
1.750% Senior Notes due September 2030 \| Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt, principal amount			$ 1,250,000,000
2.800% Senior Notes due September 2050 \| Senior Unsecured Notes
Line of Credit Facility [Line Items]
Debt, principal amount			$ 750,000,000

Debt - Summary of Issued Senior Unsecured Notes (Details) - Senior Unsecured Notes - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 1,979.6	$ 1,978.5
1.750% Senior Notes due September 2030
Debt Instrument [Line Items]
Long-term debt	$ 1,239.6	1,238.7
Interest rate	1.75%
2.800% Senior Notes due September 2050
Debt Instrument [Line Items]
Long-term debt	$ 740.0	$ 739.8
Interest rate	2.80%