Vertex Pharmaceuticals (VRTX) 10-Q 3 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Oct. 29, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	000-19319
Entity Registrant Name	VERTEX PHARMACEUTICALS INC / MA
Entity Incorporation, State or Country Code	MA
Entity Tax Identification Number	04-3039129
Entity Address, Address Line One	50 Northern Avenue
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02210
City Area Code	617
Local Phone Number	341-6100
Title of 12(b) Security	Common Stock, $0.01 Par Value Per Share
Trading Symbol	VRTX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		254,251,938
Entity Central Index Key	0000875320
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues:
Revenues	$ 1,984,164	$ 1,538,271	$ 5,501,839	$ 4,577,863
Costs and expenses:
Cost of sales	236,512	186,182	656,813	533,199
Research and development expenses	493,751	493,497	2,356,814	1,362,953
Selling, general and administrative expenses	198,189	184,551	584,935	558,613
Change in fair value of contingent consideration	1,200	1,800	(1,100)	12,600
Total costs and expenses	929,652	866,030	3,597,462	2,467,365
Income from operations	1,054,512	672,241	1,904,377	2,110,498
Interest income	1,116	3,100	3,714	19,919
Interest expense	(15,255)	(13,856)	(46,411)	(41,863)
Other income (expense), net	42,368	84,386	(2,234)	139,621
Income before provision for income taxes	1,082,741	745,871	1,859,446	2,228,175
Provision for income taxes	230,813	78,437	287,456	120,718
Net income	$ 851,928	$ 667,434	$ 1,571,990	$ 2,107,457
Net income per common share:
Basic (in dollars per share)	$ 3.30	$ 2.56	$ 6.08	$ 8.10
Diluted (in dollars per share)	$ 3.28	$ 2.53	$ 6.03	$ 7.98
Shares used in per share calculations:
Basic (in shares)	257,876	260,392	258,740	260,313
Diluted (in shares)	259,707	264,079	260,877	264,031
Product revenues, net
Revenues:
Revenues	$ 1,984,164	$ 1,536,271	$ 5,500,839	$ 4,575,863
Other revenues
Revenues:
Revenues	$ 0	$ 2,000	$ 1,000	$ 2,000

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 851,928	$ 667,434	$ 1,571,990	$ 2,107,457
Other comprehensive income (loss):
Unrealized holding (losses) gains on marketable securities, net	(56)	(1,132)	(329)	818
Unrealized gains (losses) on foreign currency forward contracts, net of tax of $(9.6) million, $7.6 million, $(21.2) million and $7.3 million, respectively	34,766	(26,313)	77,011	(27,211)
Foreign currency translation adjustment	1,986	584	3,335	(12,616)
Total other comprehensive income (loss)	36,696	(26,861)	80,017	(39,009)
Comprehensive income	$ 888,624	$ 640,573	$ 1,652,007	$ 2,068,448

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Unrealized gains (losses) on foreign currency forward contracts, tax	$ (9.6)	$ 7.6	$ (21.2)	$ 7.3

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 6,275,698	$ 5,988,187
Marketable securities	685,187	670,710
Accounts receivable, net	1,100,372	885,352
Inventories	333,456	280,777
Prepaid expenses and other current assets	457,827	308,353
Total current assets	8,852,540	8,133,379
Property and equipment, net	1,042,347	958,534
Goodwill	1,002,158	1,002,158
Intangible assets	400,000	400,000
Deferred tax assets	933,839	882,779
Operating lease assets	312,343	325,564
Other assets	75,518	49,394
Total assets	12,618,745	11,751,808
Current liabilities:
Accounts payable	127,863	155,139
Accrued expenses	1,584,992	1,404,971
Other current liabilities	201,409	317,423
Total current liabilities	1,914,264	1,877,533
Long-term finance lease liabilities	513,255	539,042
Long-term operating lease liabilities	363,545	350,463
Long-term contingent consideration	188,500	189,600
Other long-term liabilities	108,473	108,355
Total liabilities	3,088,037	3,064,993
Commitments and contingencies	0	0
Shareholders’ equity:
Preferred stock, $0.01 par value; 1,000 shares authorized; none issued and outstanding	0	0
Common stock, $0.01 par value; 500,000 shares authorized, 256,206 and 259,890 shares issued and outstanding, respectively	2,562	2,599
Additional paid-in capital	7,085,950	7,894,027
Accumulated other comprehensive income (loss)	11,537	(68,480)
Retained earnings	2,430,659	858,669
Total shareholders’ equity	9,530,708	8,686,815
Total liabilities and shareholders’ equity	$ 12,618,745	$ 11,751,808

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	256,206,000	259,890,000
Common stock, shares outstanding (in shares)	256,206,000	259,890,000

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings (Accumulated Deficit)
Beginning balance (in shares) at Dec. 31, 2019		258,993
Beginning balance at Dec. 31, 2019	$ 6,085,244	$ 2,589	$ 7,937,606	$ (1,973)	$ (1,852,978)
Increase (Decrease) in Stockholders' Equity
Other comprehensive income loss, net of tax	(39,009)			(39,009)
Net income	2,107,457				2,107,457
Repurchase of common stock (in shares)		(1,807)
Repurchase of common stock	(408,033)	$ (18)	(408,015)
Common stock withheld for employee tax obligations (in shares)		(727)
Common stock withheld for employee tax obligations	(179,775)	$ (7)	(179,768)
Issuance of common stock under benefit plans (in shares)		3,715
Issuance of common stock under benefit plans	232,079	$ 37	232,042
Stock-based compensation expense	335,510		335,510
Ending balance (in shares) at Sep. 30, 2020		260,174
Ending balance at Sep. 30, 2020	8,133,473	$ 2,601	7,917,375	(40,982)	254,479
Beginning balance (in shares) at Jun. 30, 2020		260,124
Beginning balance at Jun. 30, 2020	7,519,242	$ 2,601	7,943,717	(14,121)	(412,955)
Increase (Decrease) in Stockholders' Equity
Other comprehensive income loss, net of tax	(26,861)			(26,861)
Net income	667,434				667,434
Repurchase of common stock (in shares)		(403)
Repurchase of common stock	(108,007)	$ (4)	(108,003)
Common stock withheld for employee tax obligations (in shares)		(141)
Common stock withheld for employee tax obligations	(40,528)	$ (1)	(40,527)
Issuance of common stock under benefit plans (in shares)		594
Issuance of common stock under benefit plans	21,704	$ 5	21,699
Stock-based compensation expense	100,489		100,489
Ending balance (in shares) at Sep. 30, 2020		260,174
Ending balance at Sep. 30, 2020	8,133,473	$ 2,601	7,917,375	(40,982)	254,479
Beginning balance (in shares) at Dec. 31, 2020		259,890
Beginning balance at Dec. 31, 2020	8,686,815	$ 2,599	7,894,027	(68,480)	858,669
Increase (Decrease) in Stockholders' Equity
Other comprehensive income loss, net of tax	80,017			80,017
Net income	1,571,990				1,571,990
Repurchase of common stock (in shares)		(5,282)
Repurchase of common stock	(1,067,225)	$ (53)	(1,067,172)
Common stock withheld for employee tax obligations (in shares)		(633)
Common stock withheld for employee tax obligations	(134,223)	$ (6)	(134,217)
Issuance of common stock under benefit plans (in shares)		2,231
Issuance of common stock under benefit plans	66,729	$ 22	66,707
Stock-based compensation expense	326,605		326,605
Ending balance (in shares) at Sep. 30, 2021		256,206
Ending balance at Sep. 30, 2021	9,530,708	$ 2,562	7,085,950	11,537	2,430,659
Beginning balance (in shares) at Jun. 30, 2021		259,114
Beginning balance at Jun. 30, 2021	9,196,396	$ 2,591	7,640,233	(25,159)	1,578,731
Increase (Decrease) in Stockholders' Equity
Other comprehensive income loss, net of tax	36,696			36,696
Net income	851,928				851,928
Repurchase of common stock (in shares)		(3,293)
Repurchase of common stock	(642,273)	$ (33)	(642,240)
Common stock withheld for employee tax obligations (in shares)		(144)
Common stock withheld for employee tax obligations	(28,559)	$ (1)	(28,558)
Issuance of common stock under benefit plans (in shares)		529
Issuance of common stock under benefit plans	12,867	$ 5	12,862
Stock-based compensation expense	103,653		103,653
Ending balance (in shares) at Sep. 30, 2021		256,206
Ending balance at Sep. 30, 2021	$ 9,530,708	$ 2,562	$ 7,085,950	$ 11,537	$ 2,430,659

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net income	$ 1,571,990	$ 2,107,457
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation expense	322,792	332,434
Depreciation expense	91,768	80,160
(Decrease) increase in fair value of contingent consideration	(1,100)	12,600
Deferred income taxes	(112,654)	65,110
Gains on equity securities	(4,993)	(140,866)
Other non-cash items, net	20,588	52,371
Changes in operating assets and liabilities:
Accounts receivable, net	(231,166)	(151,191)
Inventories	(65,827)	(94,907)
Prepaid expenses and other assets	(107,672)	(264,909)
Accounts payable	(22,043)	16,153
Accrued expenses	254,157	451,084
Other liabilities	(67,333)	296,477
Net cash provided by operating activities	1,648,507	2,761,973
Cash flows from investing activities:
Purchases of available-for-sale debt securities	(447,759)	(246,937)
Maturities of available-for-sale debt securities	452,133	184,419
Purchases of property and equipment	(173,285)	(212,109)
Investment in equity securities and notes receivable	(37,991)	(19,327)
Sale of equity securities	0	149,595
Net cash used in investing activities	(206,902)	(144,359)
Cash flows from financing activities:
Issuances of common stock under benefit plans	67,289	234,854
Repurchases of common stock	(1,057,225)	(408,033)
Payments in connection with common stock withheld for employee tax obligations	(134,223)	(179,775)
Payments on finance leases	(34,592)	(31,378)
Proceeds from finance leases	12,647	8,642
Other financing activities	4,339	(4,399)
Net cash used in financing activities	(1,141,765)	(380,089)
Effect of changes in exchange rates on cash	(8,472)	2,779
Net increase in cash, cash equivalents and restricted cash	291,368	2,240,304
Cash, cash equivalents and restricted cash—beginning of period	5,988,845	3,120,681
Cash, cash equivalents and restricted cash—end of period	6,280,213	5,360,985
Supplemental disclosure of cash flow information:
Cash paid for interest	42,698	40,769
Cash paid for income taxes	$ 381,533	$ 81,684

Basis of Presentation and Accou

Basis of Presentation and Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation and Accounting Policies	Basis of Presentation and Accounting Policies Basis of Presentation The accompanying condensed consolidated financial statements are unaudited and have been prepared by Vertex Pharmaceuticals Incorporated (“Vertex” or the “Company”) in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The condensed consolidated financial statements reflect the operations of the Company and its wholly-owned subsidiaries. All material intercompany balances and transactions have been eliminated. The Company operates in one segment, pharmaceuticals. The Company has reclassified certain items from the prior year’s condensed consolidated financial statements to conform to the current year’s presentation. Certain information and footnote disclosures normally included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 (the “2020 Annual Report on Form 10-K”) have been condensed or omitted. These interim financial statements, in the opinion of management, reflect all normal recurring adjustments necessary for a fair presentation of the financial position and results of operations for the interim periods ended September 30, 2021 and 2020. The results of operations for the interim periods are not necessarily indicative of the results of operations to be expected for the full fiscal year. These interim financial statements should be read in conjunction with the audited financial statements for the year ended December 31, 2020, which are contained in the Company’s 2020 Annual Report on Form 10-K. Use of Estimates The preparation of condensed consolidated financial statements in accordance with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the amounts of revenues and expenses during the reported periods. The Company bases its estimates on historical experience and various other assumptions, including in certain circumstances future projections that management believes to be reasonable under the circumstances. Actual results could differ from those estimates. Changes in estimates are reflected in reported results in the period in which they become known. Recently Adopted and Issued Accounting Standards Income Taxes In 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740) (“ASU 2019-12”), which simplifies the accounting for income taxes. ASU 2019-12 became effective on January 1, 2021. The adoption of ASU 2019-12 did not have a significant impact on the Company’s condensed consolidated financial statements. For a discussion of other recent accounting pronouncements please refer to Note A, “Nature of Business and Accounting Policies,” in the Company’s 2020 Annual Report on Form 10-K. Summary of Significant Accounting Policies The Company’s significant accounting policies are described in Note A, “Nature of Business and Accounting Policies,” in its 2020 Annual Report on Form 10-K.

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition Disaggregation of Revenue Revenues by Product Product revenues, net consisted of the following: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) TRIKAFTA/KAFTRIO $ 1,555,772 $ 960,308 $ 4,004,600 $ 2,773,256 SYMDEKO/SYMKEVI 81,415 156,178 339,969 501,066 ORKAMBI 184,561 225,919 624,224 692,038 KALYDECO 162,416 193,866 532,046 609,503 Total product revenues, net $ 1,984,164 $ 1,536,271 $ 5,500,839 $ 4,575,863 Product Revenues by Geographic Location Total net product revenues by geographic region, based on the location of the customer, consisted of the following: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) United States $ 1,382,892 $ 1,222,565 $ 3,893,245 $ 3,620,467 Outside of the United States Europe 518,826 251,366 1,382,701 766,438 Other 82,446 62,340 224,893 188,958 Total product revenues outside of the United States 601,272 313,706 1,607,594 955,396 Total product revenues, net $ 1,984,164 $ 1,536,271 $ 5,500,839 $ 4,575,863 Contract Liabilities The Company had contract liabilities of $104.1 million and $191.5 million as of September 30, 2021 and December 31, 2020, respectively, related to annual contracts with government-owned and supported customers in international markets that limit the amount of annual reimbursement the Company can receive. Upon exceeding the annual reimbursement amount, products are provided free of charge, which is a material right. These contracts include upfront payments and fees. The Company defers a portion of the consideration received for shipments made up to the annual reimbursement limit as a portion of “Other current liabilities.” The deferred amount is recognized as revenue when the free products are shipped. The Company’s product revenue contracts include performance obligations that are one year or less. The Company’s contract liabilities at the end of each fiscal year relate to contracts with annual reimbursement limits in international markets in which the annual period associated with the contract is not the same as the Company’s fiscal year. In these markets, the Company recognizes revenues related to performance obligations satisfied in previous years; however, these revenues do not relate to any performance obligations that were satisfied more than 12 months prior to the beginning of the current year.

Collaborative Arrangements

Collaborative Arrangements	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaborative Arrangements	Collaborative Arrangements The Company has entered into numerous agreements pursuant to which it collaborates with third parties on research, development and commercialization programs, including in-license and out-license agreements. The Company’s in-license and out-license agreements that had a significant impact on its financial statements for the three and nine months ended September 30, 2021 and 2020, or were new or materially revised during the nine months ended September 30, 2021, are described below. Additional in-license and out-license agreements were described in Note B, “Collaborative Arrangements,” of the Company’s 2020 Annual Report on Form 10-K. In-license Agreements The Company has entered into a number of in-license agreements in order to advance and obtain access to technologies and services related to its research and early-development activities. The Company is generally required to make an upfront payment upon execution of the license agreement; development, regulatory and commercialization milestones payments upon the achievement of certain product research, development and commercialization objectives; and royalty payments on future sales, if any, of commercial products resulting from the collaboration. Pursuant to the terms of its in-license agreements, the Company’s collaborators typically lead the discovery efforts and the Company leads all preclinical, development and commercialization activities associated with the advancement of any drug candidates and funds all expenses. The Company typically can terminate its in-license agreements by providing advance notice to its collaborators; the required length of notice is dependent on whether any product developed under the license agreement has received marketing approval. The Company’s license agreements may be terminated by either party for a material breach by the other, subject to notice and cure provisions. Unless earlier terminated, these license agreements generally remain in effect until the date on which the royalty term and all payment obligations with respect to all products in all countries have expired. The Company’s “Research and development expenses” included $26.8 million and $986.8 million for the three and nine months ended September 30, 2021, respectively, and $80.1 million and $143.3 million for the three and nine months ended September 30, 2020, respectively, related to upfront and milestone payments pursuant to its in-license agreements. CRISPR Therapeutics AG - CRISPR-Cas9 Gene-editing Therapies In 2015, the Company entered into a strategic collaboration, option and license agreement (the “CRISPR Agreement”) with CRISPR Therapeutics AG and its affiliates (“CRISPR”) to collaborate on the discovery and development of potential new treatments aimed at the underlying genetic causes of human diseases using CRISPR-Cas9 gene-editing technology. The Company had the exclusive right to license certain targets. In 2019, the Company elected to exclusively license three targets, including cystic fibrosis, pursuant to the CRISPR Agreement. For each of the three targets that the Company elected to license, CRISPR has the potential to receive up to an additional $410.0 million in development, regulatory and commercial milestones as well as royalties on net product sales. In 2017, the Company entered into a joint development and commercialization agreement with CRISPR pursuant to the terms of the CRISPR Agreement (the “Original CTX001 JDCA”), under which the Company and CRISPR were co-developing and preparing to co-commercialize CTX001 for the treatment of hemoglobinopathies, including treatments for sickle cell disease and beta thalassemia. In the second quarter of 2021, the Company and CRISPR amended and restated the Original CTX001 JDCA (the “A&R JDCA”), pursuant to which the parties agreed to, among other things, (a) adjust the governance structure for the collaboration and adjust the responsibilities of each party thereunder; (b) adjust the allocation of net profits and net losses between the parties; and (c) exclusively license (subject to CRISPR’s reserved rights to conduct certain activities) certain intellectual property rights to the Company relating to the products that may be researched, developed, manufactured and commercialized under such agreement. Pursuant to the A&R JDCA, the Company is now leading global development, manufacturing and commercialization of CTX001, with support from CRISPR. Subject to the terms and conditions of the A&R JDCA, the Company also has the right to conduct all research, development, manufacturing and commercialization activities relating to the product candidates and products under the A&R JDCA (including CTX001) throughout the world subject to CRISPR’s reserved right to conduct certain activities. In connection with the amendment and restatement of this agreement, the Company made a $900.0 million upfront payment to CRISPR in the second quarter of 2021. The Company concluded that it did not have any alternative future use for the acquired in-process research and development and recorded this upfront payment to “Research and development expenses.” CRISPR has the potential to receive an additional one-time $200.0 million milestone payment upon receipt of the first marketing approval of CTX001 from the U.S. Food or Drug Administration or the European Commission. The Company and CRISPR shared equally all expenses incurred under the Original CTX001 JDCA. On July 1, 2021, with respect to CTX001, the net profits and net losses incurred pursuant to the A&R JDCA began to be allocated 60% to the Company and 40% to CRISPR, while all other product candidates and products continued to have net profits and net losses shared equally between the parties. The Company concluded that the Original CTX001 JDCA and the A&R JDCA are cost-sharing arrangements, which result in the net impact of the arrangements being recorded in “Research and development expenses” in its condensed consolidated statements of operations. During the three and nine months ended September 30, 2021 and 2020, the Company recognized the following amounts in total related to these agreements: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Total research and development expenses incurred under the Original CTX001 JDCA and A&R JDCA $ 58,659 $ 28,623 $ 147,448 $ 66,720 Vertex’s share recognized in research and development expenses in condensed consolidated statement of operations 35,195 14,311 79,590 33,360 Moderna, Inc. In 2016, the Company entered into a strategic collaboration and licensing agreement with Moderna, Inc. (“Moderna”), pursuant to which the parties are seeking to identify and develop messenger ribonucleic acid (“mRNA”) therapeutics for the treatment of CF. In September 2020, the Company entered into a new strategic collaboration and licensing agreement with Moderna (the “2020 Moderna Agreement”) aimed at the discovery and development of lipid nanoparticles and mRNAs that can deliver gene-editing therapies to lung cells for the treatment of CF. Pursuant to the 2020 Moderna Agreement, Moderna received an upfront payment of $75.0 million and is eligible to receive up to $380.0 million in development, regulatory and commercial milestones as well as royalties on net product sales. The Company determined that substantially all of the fair value of the 2020 Moderna Agreement was attributable to in-process research and development and no substantive processes were acquired that would constitute a business. The Company concluded that it did not have any alternative future use for the acquired in-process research and development and recorded the upfront payment to “Research and development expenses” in the third quarter of 2020. Out-license Agreements The Company has entered into licensing agreements pursuant to which it has out-licensed rights to certain drug candidates to third-party collaborators. Pursuant to these out-license agreements, the Company’s collaborators become responsible for all costs related to the continued development of such drug candidates and obtain development and commercialization rights to these drug candidates. Depending on the terms of the agreements, the Company’s collaborators may be required to make upfront payments, milestone payments upon the achievement of certain product research and development objectives an d may also be required to pay royalties on future sales, if any, of commercial products resulting from the collaboration. The termination provisions associated with these collaborations are generally the same as those described above related to the Company’s in-license agreements. None of the Company’s out-license agreements had a significant impact on the Company’s condensed consolidated statement of operations during the three and nine months ended September 30, 2021 and 2020.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share Basic net income per common share is based upon the weighted-average number of common shares outstanding during the period. Diluted net income per common share utilizing the treasury-stock method is based upon the weighted-average number of common shares outstanding during the period plus additional weighted-average common equivalent shares outstanding during the period when the effect is dilutive. The following table sets forth the computation of basic and diluted net income per common share for the periods ended: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands, except per share amounts) Net income $ 851,928 $ 667,434 $ 1,571,990 $ 2,107,457 Basic weighted-average common shares outstanding 257,876 260,392 258,740 260,313 Effect of potentially dilutive securities: Stock options 971 1,887 1,124 1,936 Restricted stock units (including PSUs) 841 1,788 1,003 1,765 Employee stock purchase program 19 12 10 17 Diluted weighted-average common shares outstanding 259,707 264,079 260,877 264,031 Basic net income per common share $ 3.30 $ 2.56 $ 6.08 $ 8.10 Diluted net income per common share $ 3.28 $ 2.53 $ 6.03 $ 7.98 The Company did not include the securities in the following table in the computation of the net income per common share because the effect would have been anti-dilutive during each period: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Stock options 1,060 23 711 303 Unvested restricted stock units (including PSUs) 204 252 440 229

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The following fair value hierarchy is used to classify assets and liabilities based on observable inputs and unobservable inputs used in order to determine the fair value of the Company’s financial assets and liabilities: Level 1: Quoted prices in active markets for identical assets or liabilities. An active market for an asset or liability is a market in which transactions for the asset or liability occur with sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2: Observable inputs other than Level 1 inputs. Examples of Level 2 inputs include quoted prices in active markets for similar assets or liabilities and quoted prices for identical assets or liabilities in markets that are not active. Level 3: Unobservable inputs based on the Company’s assessment of the assumptions that market participants would use in pricing the asset or liability. The Company’s investment strategy is focused on capital preservation. The Company invests in instruments that meet the credit quality standards outlined in the Company’s investment policy. This policy also limits the amount of credit exposure to any one issue or type of instrument. The Company maintains strategic investments separately from the investment policy that governs its other cash, cash equivalents and marketable securities as described in Note F, “Marketable Securities and Equity Investments.” Additionally, the Company utilizes foreign currency forward contracts intended to mitigate the effect of changes in foreign exchange rates on its condensed consolidated statement of operations. During the three and nine months ended September 30, 2021 and 2020, the Company did not record any other-than-temporary impairment charges related to its financial assets. The following tables set forth the Company’s financial assets and liabilities subject to fair value measurements by level within the fair value hierarchy (and does not include $2.7 billion and $2.8 billion of cash as of September 30, 2021 and December 31, 2020, respectively): As of September 30, 2021 As of December 31, 2020 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 (in thousands) Financial instruments carried at fair value (asset positions): Cash equivalents: Money market funds $ 3,578,764 $ 3,578,764 $ — $ — $ 3,141,053 $ 3,141,053 $ — $ — Commercial paper 31,998 — 31,998 — — — — — Marketable securities: Corporate equity securities 218,764 218,764 — — 195,781 15,650 180,131 — U.S. Treasury securities 46,539 46,539 — — — — — — Government-sponsored enterprise securities 69,002 69,002 — — 80,063 80,063 — — Corporate debt securities 95,359 — 95,359 — 231,598 — 231,598 — Commercial paper 255,523 — 255,523 — 163,268 — 163,268 — Prepaid expenses and other current assets: Foreign currency forward contracts 34,300 — 34,300 — — — — — Other assets: Foreign currency forward contracts 4,781 — 4,781 — — — — — Total financial assets $ 4,335,030 $ 3,913,069 $ 421,961 $ — $ 3,811,763 $ 3,236,766 $ 574,997 $ — Financial instruments carried at fair value (liability positions): Other current liabilities: Foreign currency forward contracts $ (4,356) $ — $ (4,356) $ — $ (59,184) $ — $ (59,184) $ — Long-term contingent consideration (188,500) — — (188,500) (189,600) — — (189,600) Other long-term liabilities: Foreign currency forward contracts (29) — (29) — (4,283) — (4,283) — Total financial liabilities $ (192,885) $ — $ (4,385) $ (188,500) $ (253,067) $ — $ (63,467) $ (189,600) Please refer to Note F, “Marketable Securities and Equity Investments,” for the carrying amount and related unrealized gains (losses) by type of investment. Fair Value of Corporate Equity Securities The Company classifies its investments in publicly traded corporate equity securities as “Marketable securities” on its condensed consolidated balance sheets. Generally, the Company’s investments in the common stock of these publicly traded companies are valued based on Level 1 inputs because they have readily determinable fair values. However, certain of the Company’s investments in publicly traded companies have been or continue to be valued based on Level 2 inputs due to transfer restrictions associated with these investments. Please refer to Note F, “Marketable Securities and Equity Investments,” for further information on these investments. Fair Value of Contingent Consideration In 2019, the Company acquired Exonics Therapeutics, Inc. (“Exonics”), a privately-held company focused on creating transformative gene-editing therapies to repair mutations that cause DMD and other severe neuromuscular diseases, including DM1. The Company’s Level 3 contingent consideration liabilities are related to $678.3 million of development and regulatory milestones potentially payable to Exonics’ former equity holders. The Company bases its estimates of the probability of achieving the milestones relevant to the fair value of contingent payments on industry data attributable to rare diseases. The discount rates used in the valuation model for contingent payments, which were between 0.3% and 2.2% as of September 30, 2021, represent a measure of credit risk and market risk associated with settling the liabilities. Significant judgment is used in determining the appropriateness of these assumptions at each reporting period. Due to the uncertainties associated with development and commercialization of drug candidates in the pharmaceutical industry and the effects of changes in other assumptions including discount rates, the Company expects its estimates regarding the fair value of contingent consideration to change in the future, resulting in adjustments to the fair value of the Company’s contingent consideration liabilities, and the effect of any such adjustments could be material. The following table represents a rollforward of the fair value of the Company’s contingent consideration liabilities: Nine Months Ended September 30, 2021 (in thousands) Balance at December 31, 2020 $ 189,600 Decrease in fair value of contingent payments (1,100) Balance at September 30, 2021 $ 188,500

Marketable Securities and Equit

Marketable Securities and Equity Investments	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Marketable Securities and Equity Investments	Marketable Securities and Equity Investments A summary of the Company’s cash equivalents and marketable securities, which are recorded at fair value (and do not include $2.7 billion and $2.8 billion of cash as of September 30, 2021 and December 31, 2020, respectively), is shown below: As of September 30, 2021 As of December 31, 2020 Amortized Cost Gross Gross Fair Value Amortized Cost Gross Gross Fair Value (in thousands) Cash equivalents: Money market funds $ 3,578,764 $ — $ — $ 3,578,764 $ 3,141,053 $ — $ — $ 3,141,053 Commercial paper 31,997 1 — 31,998 — — — — Total cash equivalents $ 3,610,761 $ 1 $ — $ 3,610,762 $ 3,141,053 $ — $ — $ 3,141,053 Marketable securities: U.S. Treasury securities $ 46,536 $ 4 $ (1) $ 46,539 $ — $ — $ — $ — Government-sponsored enterprise securities 68,996 8 (2) 69,002 80,046 17 — 80,063 Corporate debt securities 95,385 26 (52) 95,359 231,263 377 (42) 231,598 Commercial paper 255,501 40 (18) 255,523 163,286 19 (37) 163,268 Total marketable debt securities 466,418 78 (73) 466,423 474,595 413 (79) 474,929 Corporate equity securities 69,418 150,263 (917) 218,764 51,427 144,354 — 195,781 Total marketable securities $ 535,836 $ 150,341 $ (990) $ 685,187 $ 526,022 $ 144,767 $ (79) $ 670,710 Available-for-sale debt securities were classified on the Company's condensed consolidated balance sheets at fair value as follows: As of September 30, 2021 As of December 31, 2020 (in thousands) Cash and cash equivalents $ 3,610,762 $ 3,141,053 Marketable securities 466,423 474,929 Total $ 4,077,185 $ 3,615,982 Available-for-sale debt securities by contractual maturity were as follows: As of September 30, 2021 As of December 31, 2020 (in thousands) Matures within one year $ 4,014,441 $ 3,526,185 Matures after one year through five years 62,744 89,797 Total $ 4,077,185 $ 3,615,982 The Company has a limited number of available-for-sale debt securities in insignificant loss positions as of September 30, 2021, which it does not intend to sell and has concluded it will not be required to sell before recovery of the amortized costs for the investments at maturity. The Company did not record any charges for other-than-temporary declines in the fair value of available-for-sale debt securities or gross realized gains or losses in the three and nine months ended September 30, 2021 and 2020. The Company records changes in the fair value of its investments in corporate equity securities to “Other income (expense), net” on its condensed consolidated statements of operations. During the three and nine months ended September 30, 2021 and 2020, the Company’s net unrealized gains on corporate equity securities held at the conclusion of each period were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Net unrealized gains $ 46,679 $ 69,834 $ 4,993 $ 102,317 During the nine months ended September 30, 2020, the Company received proceeds of $149.6 million related to the sale of the common stock of publicly traded companies, which had a total original weighted-average cost basis of $51.3 million. There were no sales of the common stock of publicly traded companies during the nine months ended September 30, 2021. As of September 30, 2021, the carrying value of the Company’s equity investments without readily determinable fair values, which are recorded in “Other assets” on its condensed consolidated balance sheets, was $35.9 million.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) The following table summarizes the changes in accumulated other comprehensive income (loss) by component: Foreign Currency Translation Adjustment Unrealized Holding Gains (Losses), Net of Tax Total On Available-For-Sale Debt Securities On Foreign Currency Forward Contracts (in thousands) Balance at December 31, 2020 $ (15,678) $ 334 $ (53,136) $ (68,480) Other comprehensive income (loss) before reclassifications 3,335 (329) 46,175 49,181 Amounts reclassified from accumulated other comprehensive (loss) income — — 30,836 30,836 Net current period other comprehensive income (loss) 3,335 (329) 77,011 80,017 Balance at September 30, 2021 $ (12,343) $ 5 $ 23,875 $ 11,537 Balance at December 31, 2019 $ (895) $ 503 $ (1,581) $ (1,973) Other comprehensive (loss) income before reclassifications (12,616) 818 (20,913) (32,711) Amounts reclassified from accumulated other comprehensive loss — — (6,298) (6,298) Net current period other comprehensive (loss) income (12,616) 818 (27,211) (39,009) Balance at September 30, 2020 $ (13,511) $ 1,321 $ (28,792) $ (40,982)

Hedging

Hedging	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Hedging	Hedging Foreign currency forward contracts - Designated as hedging instruments The Company maintains a hedging program intended to mitigate the effect of changes in foreign exchange rates for a portion of the Company’s forecasted product revenues denominated in certain foreign currencies. The program includes foreign currency forward contracts that are designated as cash flow hedges under U.S. GAAP having contractual durations from one The Company formally documents the relationship between foreign currency forward contracts (hedging instruments) and forecasted product revenues (hedged items), as well as the Company’s risk management objective and strategy for undertaking various hedging activities, which includes matching all foreign currency forward contracts that are designated as cash flow hedges to forecasted transactions. The Company also formally assesses, both at the hedge’s inception and on an ongoing basis, whether the foreign currency forward contracts are highly effective in offsetting changes in cash flows of hedged items on a prospective and retrospective basis. If the Company were to determine that a (i) foreign currency forward contract is not highly effective as a cash flow hedge, (ii) foreign currency forward contract has ceased to be a highly effective hedge or (iii) forecasted transaction is no longer probable of occurring, the Company would discontinue hedge accounting treatment prospectively. The Company measures effectiveness based on the change in fair value of the forward contracts and the fair value of the hypothetical foreign currency forward contracts with terms that match the critical terms of the risk being hedged. As of September 30, 2021, all hedges were determined to be highly effective. The Company considers the impact of its counterparties’ credit risk on the fair value of the foreign currency forward contracts. As of September 30, 2021 and December 31, 2020, credit risk did not change the fair value of the Company’s foreign currency forward contracts. The following table summarizes the notional amount in U.S. dollars of the Company’s outstanding foreign currency forward contracts designated as cash flow hedges under U.S. GAAP: As of September 30, 2021 As of December 31, 2020 Foreign Currency (in thousands) Euro $ 1,194,338 $ 745,099 British pound sterling 277,815 160,427 Australian dollar 95,970 99,922 Canadian dollar 87,259 86,468 Swiss Franc 41,335 — Total foreign currency forward contracts $ 1,696,717 $ 1,091,916 Foreign currency forward contracts - Not designated as hedging instruments The Company also enters into foreign currency forward contracts with contractual maturities of less than one month, which are designed to mitigate the effect of changes in foreign exchange rates on monetary assets and liabilities, including intercompany balances. These contracts are not designated as hedging instruments under U.S. GAAP. The Company recognizes realized gains and losses for such contracts in “Other income (expense), net” in its condensed consolidated statements of operations each period. As of September 30, 2021, the notional amount of the Company’s outstanding foreign currency forward contracts where hedge accounting under U.S. GAAP is not applied was $306.2 million. During the three and nine months ended September 30, 2021 and 2020, the Company recognized the following related to foreign currency forward contracts in its condensed consolidated statements of operations: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Designated as hedging instruments - Reclassified from AOCI Product revenues, net $ (5,224) $ (7,249) $ (39,342) $ 8,039 Not designated as hedging instruments Other income (expense), net $ (400) $ 25,897 $ (9,350) $ 15,724 Total reported in the Condensed Consolidated Statement of Operations Product revenues, net $ 1,984,164 $ 1,536,271 $ 5,500,839 $ 4,575,863 Other income (expense), net $ 42,368 $ 84,386 $ (2,234) $ 139,621 The following table summarizes the fair value of the Company’s outstanding foreign currency forward contracts designated as cash flow hedges under U.S. GAAP included on its condensed consolidated balance sheets: As of September 30, 2021 Assets Liabilities Classification Fair Value Classification Fair Value (in thousands) Prepaid expenses and other current assets $ 34,300 Other current liabilities $ (4,356) Other assets 4,781 Other long-term liabilities (29) Total assets $ 39,081 Total liabilities $ (4,385) As of December 31, 2020 Assets Liabilities Classification Fair Value Classification Fair Value (in thousands) Prepaid expenses and other current assets $ — Other current liabilities $ (59,184) Other assets — Other long-term liabilities (4,283) Total assets $ — Total liabilities $ (63,467) As of September 30, 2021, the Company expects the amounts that are related to foreign exchange forward contracts designated as cash flow hedges under U.S. GAAP recorded in “Prepaid expenses and other current assets” and “Other current liabilities” to be reclassified to earnings within twelve months. The following table summarizes the potential effect of offsetting derivatives by type of financial instrument designated as cash flow hedges under U.S. GAAP on the Company’s condensed consolidated balance sheets: As of September 30, 2021 Gross Amounts Recognized Gross Amounts Offset Gross Amounts Presented Gross Amounts Not Offset Legal Offset Foreign currency forward contracts (in thousands) Total assets $ 39,081 $ — $ 39,081 $ (4,385) $ 34,696 Total liabilities (4,385) — (4,385) 4,385 — As of December 31, 2020 Gross Amounts Recognized Gross Amounts Offset Gross Amounts Presented Gross Amounts Not Offset Legal Offset Foreign currency forward contracts (in thousands) Total assets $ — $ — $ — $ — $ — Total liabilities (63,467) — (63,467) — (63,467)

Inventories

Inventories	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consisted of the following: As of September 30, 2021 As of December 31, 2020 (in thousands) Raw materials $ 45,990 $ 46,232 Work-in-process 192,650 161,324 Finished goods 94,816 73,221 Total $ 333,456 $ 280,777

Stock-based Compensation Expens

Stock-based Compensation Expense and Share Repurchase Programs	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock-based Compensation Expense and Share Repurchase Programs	Stock-based Compensation Expense and Share Repurchase Programs Stock-based compensation expense During the three and nine months ended September 30, 2021 and 2020, the Company recognized the following stock-based compensation expense: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Stock-based compensation expense by type of award: Restricted stock units (including PSUs) and restricted stock $ 89,458 $ 84,043 $ 279,131 $ 279,611 Stock options 7,875 13,221 29,580 47,334 ESPP share issuances 6,321 3,225 17,895 8,565 Stock-based compensation expense related to inventories (658) (950) (3,814) (3,076) Total stock-based compensation expense included in costs and expenses $ 102,996 $ 99,539 $ 322,792 $ 332,434 Stock-based compensation expense by line item: Cost of sales $ 1,599 $ 1,250 $ 4,570 $ 3,998 Research and development expenses 60,995 60,770 196,412 203,732 Selling, general and administrative expenses 40,402 37,519 121,810 124,704 Total stock-based compensation expense included in costs and expenses 102,996 99,539 322,792 332,434 Income tax effect (21,556) (35,295) (73,663) (130,692) Total stock-based compensation expense, net of tax $ 81,440 $ 64,244 $ 249,129 $ 201,742 Share repurchase programs In 2019, the Company’s Board of Directors approved a share repurchase program (the “2019 Share Repurchase Program”), pursuant to which the Company repurchased $500.0 million of its common stock in 2019 and 2020. During the nine months ended September 30, 2020, the Company repurchased 1,806,587 shares of its common stock under the 2019 Share Repurchase Program for an aggregate of $408.0 million. In November 2020, the Company’s Board of Directors approved a share repurchase program (the “2020 Share Repurchase Program”), pursuant to which the Company repurchased $500.0 million of its common stock in 2020 and the first quarter of 2021. During the three months ended March 31, 2021, the Company repurchased 1,988,941 shares of its common stock under the 2020 Share Repurchase Program for an aggregate of $424.9 million. On June 23, 2021, the Company’s Board of Directors approved a new share repurchase program (the “2021 Share Repurchase Program”), pursuant to which the Company is authorized to repurchase up to $1.5 billion of its common stock by December 31, 2022. During the three months ended September 30, 2021, the Company repurchased 3,293,161 shares of its common stock under the 2021 Share Repurchase Program for an aggregate of $642.2 million. As of September 30, 2021, a total of $857.8 million remained available under this program.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is subject to U.S. federal, state, and foreign income taxes. During the three and nine months ended September 30, 2021 and 2020, the Company recorded the following provisions for income taxes and effective tax rates as compared to its income before provision for income taxes: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands, except percentages) Income before provision for income taxes $ 1,082,741 $ 745,871 $ 1,859,446 $ 2,228,175 Provision for income taxes 230,813 78,437 287,456 120,718 Effective tax rate 21 % 11 % 15 % 5 % The Company’s effective tax rate for the three months ended September 30, 2021 was similar to the U.S. statutory rate. The Company’s effective tax rate for the nine months ended September 30, 2021 was lower than the U.S. statutory rate primarily due to a $99.7 million discrete tax benefit associated with an increase in the U.K.’s corporate tax rate from 19% to 25%, which was enacted in June 2021 and will become effective in April 2023. The Company’s effective tax rate for the three months ended September 30, 2020 was lower than the U.S. statutory rate primarily due to a discrete tax benefit associated with an increase in the U.K.’s corporate tax rate from 17% to 19%, which was enacted and became effective in July 2020. The Company’s effective tax rate for the nine months ended September 30, 2020 was lower than the U.S. statutory rate due to a discrete tax benefit of $209.0 million associated with an intra-entity transfer of intellectual property rights to the U.K., a discrete benefit related to the write-off of a long-term intercompany receivable, the increase in the U.K.’s corporate tax rate from 17% to 19% noted above and excess tax benefits related to stock-based compensation. As part of the U.S. Tax Cut and Jobs Act of 2017, the Company is subject to a territorial tax system, under which it must establish an accounting policy to provide for tax on Global Intangible Low Taxed Income (“GILTI”) earned by certain foreign subsidiaries. The Company has elected to treat the impact of GILTI as a current tax expense in its provision for income taxes. The Company has reviewed the tax positions taken, or to be taken, in its tax returns for all tax years currently open to examination by a taxing authority. Unrecognized tax benefits represent the aggregate tax effect of differences between tax return positions and the benefits recognized in the consolidated financial statements. As of September 30, 2021 and December 31, 2020, the Company had $89.0 million and $75.8 million, respectively, of net unrecognized tax benefits, which would affect the Company’s tax rate if recognized. The Company does not expect that its unrecognized tax benefits will materially change within the next twelve months. As of September 30, 2021, foreign earnings have been retained by foreign subsidiaries for indefinite reinvestment. Upon repatriation of those earnings, in the form of dividends or otherwise, the Company could be subject to withholding taxes payable to the various foreign countries. The Company files U.S. federal income tax returns and income tax returns in various state, local and foreign jurisdictions. The Company has various income tax audits ongoing at any time throughout the world. The Company is no longer subject to any tax assessment from an income tax examination in the U.S. or any other major taxing jurisdiction before 2011, except where the Company has net operating losses or tax credit carryforwards that originate before 2011.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Revolving Credit Facilities The Company and certain of its subsidiaries have entered into two credit agreements (the “Credit Agreements”) with Bank of America, N.A., as administrative agent and the lenders referred to therein (the “Lenders”). The Credit Agreements were not drawn upon at closing and the Company has not drawn upon them to date. Amounts drawn pursuant to the Credit Agreements, if any, will be used for general corporate purposes. Any amounts borrowed under the Credit Agreements will bear interest, at the Company’s option, at either a base rate or a Eurocurrency rate, in each case plus an applicable margin based on the Company’s consolidated leverage ratio (the ratio of the Company’s total consolidated funded indebtedness to the Company’s consolidated EBITDA for the most recently completed four fiscal quarter period). In September 2019, the Company and certain of its subsidiaries entered into a $500.0 million unsecured revolving facility (the “2019 Credit Agreement”) with the Lenders, which matures on September 17, 2024. Under the 2019 Credit Agreement, the applicable margins on base rate loans range from 0.125% to 0.500% and the applicable margins on Eurocurrency loans range from 1.125% to 1.500%. The 2019 Credit Agreement provides a sublimit of $50.0 million for letters of credit. In September 2020, the Company and certain of its subsidiaries entered into a $2.0 billion unsecured revolving facility (the “2020 Credit Agreement”) with the Lenders, which matures on September 18, 2022. Under the 2020 Credit Agreement, the applicable margins on base rate loans range from 0.500% to 0.875% and the applicable margins on Eurocurrency loans range from 1.500% to 1.875%. The 2020 Credit Agreement does not support letters of credit. Subject to satisfaction of certain conditions, the Company may request that the borrowing capacity for each of the Credit Agreements be increased by an additional $500.0 million. Any amounts borrowed pursuant to the Credit Agreements are guaranteed by certain of the Company’s existing and future domestic subsidiaries, subject to certain exceptions. The Credit Agreements contain customary representations and warranties and affirmative and negative covenants, including financial covenants to maintain (x) subject to certain limited exceptions, a consolidated leverage ratio of 3.50 to 1.00, subject to an increase to 4.00 to 1.00 following a material acquisition and (y) a consolidated interest coverage ratio of 2.50 to 1.00, in each case measured on a quarterly basis. As of September 30, 2021, the Company was in compliance with the covenants described above. The Credit Agreements also contain customary events of default. In the case of a continuing event of default, the administrative agent would be entitled to exercise various remedies, including the acceleration of amounts due under outstanding loans. Direct costs related to the Credit Agreements are recorded over the term of the Credit Agreements and were not material to the Company’s financial statements. Guaranties and Indemnifications As permitted under Massachusetts law, the Company’s Articles of Organization and By-laws provide that the Company will indemnify certain of its officers and directors for certain claims asserted against them in connection with their service as an officer or director. The maximum potential amount of future payments that the Company could be required to make under these indemnification provisions is unlimited. However, the Company has purchased directors’ and officers’ liability insurance policies that could reduce its monetary exposure and enable it to recover a portion of any future amounts paid. No indemnification claims currently are outstanding, and the Company believes the estimated fair value of these indemnification arrangements is minimal. The Company customarily agrees in the ordinary course of its business to indemnification provisions in agreements with clinical trial investigators and sites in its drug development programs, sponsored research agreements with academic and not-for-profit institutions, various comparable agreements involving parties performing services for the Company and its real estate leases. The Company also customarily agrees to certain indemnification provisions in its drug discovery, development and commercialization collaboration agreements. With respect to the Company’s clinical trials and sponsored research agreements, these indemnification provisions typically apply to any claim asserted against the investigator or the investigator’s institution relating to personal injury or property damage, violations of law or certain breaches of the Company’s contractual obligations arising out of the research or clinical testing of the Company’s compounds or drug candidates. With respect to lease agreements, the indemnification provisions typically apply to claims asserted against the landlord relating to personal injury or property damage caused by the Company, to violations of law by the Company or to certain breaches of the Company’s contractual obligations. The indemnification provisions appearing in the Company’s collaboration agreements are similar to those for the other agreements discussed above, but in addition provide some limited indemnification for its collaborator in the event of third-party claims alleging infringement of intellectual property rights. In each of the cases above, the indemnification obligation generally survives the termination of the agreement for some extended period, although the Company believes the obligation typically has the most relevance during the contract term and for a short period of time thereafter. The maximum potential amount of future payments that the Company could be required to make under these provisions is generally unlimited. The Company has purchased insurance policies covering personal injury, property damage and general liability that reduce its exposure for indemnification and would enable it in many cases to recover all or a portion of any future amounts paid. The Company has never paid any material amounts to defend lawsuits or settle claims related to these indemnification provisions. Accordingly, the Company believes the estimated fair value of these indemnification arrangements is minimal. Other Contingencies The Company has certain contingent liabilities that arise in the ordinary course of its business activities. The Company accrues a reserve for contingent liabilities when it is probable that future expenditures will be made, and such expenditures can be reasonably estimated. Other than the Company’s contingent consideration liabilities discussed in Note E, “Fair Value Measurements,” there were no material contingent liabilities accrued as of September 30, 2021 or December 31, 2020.

Additional Cash Flow Informatio

Additional Cash Flow Information	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Additional Cash Flow Information	Additional Cash Flow Information The cash, cash equivalents and restricted cash at the beginning and ending of each period presented in the Company’s condensed consolidated statements of cash flows consisted of the following: Nine Months Ended September 30, 2021 2020 Beginning of period End of period Beginning of period End of period (in thousands) Cash and cash equivalents $ 5,988,187 $ 6,275,698 $ 3,109,322 $ 5,358,087 Prepaid expenses and other current assets 658 4,515 8,004 2,898 Other assets — — 3,355 — Cash, cash equivalents and restricted cash per condensed consolidated statement of cash flows $ 5,988,845 $ 6,280,213 $ 3,120,681 $ 5,360,985

Basis of Presentation and Acc_2

Basis of Presentation and Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements are unaudited and have been prepared by Vertex Pharmaceuticals Incorporated (“Vertex” or the “Company”) in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The condensed consolidated financial statements reflect the operations of the Company and its wholly-owned subsidiaries. All material intercompany balances and transactions have been eliminated. The Company operates in one segment, pharmaceuticals. The Company has reclassified certain items from the prior year’s condensed consolidated financial statements to conform to the current year’s presentation. Certain information and footnote disclosures normally included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 (the “2020 Annual Report on Form 10-K”) have been condensed or omitted. These interim financial statements, in the opinion of management, reflect all normal recurring adjustments necessary for a fair presentation of the financial position and results of operations for the interim periods ended September 30, 2021 and 2020.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in accordance with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the amounts of revenues and expenses during the reported periods. The Company bases its estimates on historical experience and various other assumptions, including in certain circumstances future projections that management believes to be reasonable under the circumstances. Actual results could differ from those estimates. Changes in estimates are reflected in reported results in the period in which they become known.
Recently Adopted and Issued Accounting Standards	Recently Adopted and Issued Accounting Standards Income Taxes In 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740) (“ASU 2019-12”), which simplifies the accounting for income taxes. ASU 2019-12 became effective on January 1, 2021. The adoption of ASU 2019-12 did not have a significant impact on the Company’s condensed consolidated financial statements.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue	Product revenues, net consisted of the following: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) TRIKAFTA/KAFTRIO $ 1,555,772 $ 960,308 $ 4,004,600 $ 2,773,256 SYMDEKO/SYMKEVI 81,415 156,178 339,969 501,066 ORKAMBI 184,561 225,919 624,224 692,038 KALYDECO 162,416 193,866 532,046 609,503 Total product revenues, net $ 1,984,164 $ 1,536,271 $ 5,500,839 $ 4,575,863 Total net product revenues by geographic region, based on the location of the customer, consisted of the following: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) United States $ 1,382,892 $ 1,222,565 $ 3,893,245 $ 3,620,467 Outside of the United States Europe 518,826 251,366 1,382,701 766,438 Other 82,446 62,340 224,893 188,958 Total product revenues outside of the United States 601,272 313,706 1,607,594 955,396 Total product revenues, net $ 1,984,164 $ 1,536,271 $ 5,500,839 $ 4,575,863

Collaborative Arrangements (Tab

Collaborative Arrangements (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Collaborative Arrangement on Research and Development	During the three and nine months ended September 30, 2021 and 2020, the Company recognized the following amounts in total related to these agreements: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Total research and development expenses incurred under the Original CTX001 JDCA and A&R JDCA $ 58,659 $ 28,623 $ 147,448 $ 66,720 Vertex’s share recognized in research and development expenses in condensed consolidated statement of operations 35,195 14,311 79,590 33,360

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic and diluted net income per common share for the periods ended: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands, except per share amounts) Net income $ 851,928 $ 667,434 $ 1,571,990 $ 2,107,457 Basic weighted-average common shares outstanding 257,876 260,392 258,740 260,313 Effect of potentially dilutive securities: Stock options 971 1,887 1,124 1,936 Restricted stock units (including PSUs) 841 1,788 1,003 1,765 Employee stock purchase program 19 12 10 17 Diluted weighted-average common shares outstanding 259,707 264,079 260,877 264,031 Basic net income per common share $ 3.30 $ 2.56 $ 6.08 $ 8.10 Diluted net income per common share $ 3.28 $ 2.53 $ 6.03 $ 7.98
Schedule of Potential Gross Common Equivalent Shares	The Company did not include the securities in the following table in the computation of the net income per common share because the effect would have been anti-dilutive during each period: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Stock options 1,060 23 711 303 Unvested restricted stock units (including PSUs) 204 252 440 229

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Financial Assets Subject to Fair Value Measurements (Excluding Vie Cash and Cash Equivalents, Which are Recorded as Restricted Cash and Cash Equivalents (Vie))	The following tables set forth the Company’s financial assets and liabilities subject to fair value measurements by level within the fair value hierarchy (and does not include $2.7 billion and $2.8 billion of cash as of September 30, 2021 and December 31, 2020, respectively): As of September 30, 2021 As of December 31, 2020 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 (in thousands) Financial instruments carried at fair value (asset positions): Cash equivalents: Money market funds $ 3,578,764 $ 3,578,764 $ — $ — $ 3,141,053 $ 3,141,053 $ — $ — Commercial paper 31,998 — 31,998 — — — — — Marketable securities: Corporate equity securities 218,764 218,764 — — 195,781 15,650 180,131 — U.S. Treasury securities 46,539 46,539 — — — — — — Government-sponsored enterprise securities 69,002 69,002 — — 80,063 80,063 — — Corporate debt securities 95,359 — 95,359 — 231,598 — 231,598 — Commercial paper 255,523 — 255,523 — 163,268 — 163,268 — Prepaid expenses and other current assets: Foreign currency forward contracts 34,300 — 34,300 — — — — — Other assets: Foreign currency forward contracts 4,781 — 4,781 — — — — — Total financial assets $ 4,335,030 $ 3,913,069 $ 421,961 $ — $ 3,811,763 $ 3,236,766 $ 574,997 $ — Financial instruments carried at fair value (liability positions): Other current liabilities: Foreign currency forward contracts $ (4,356) $ — $ (4,356) $ — $ (59,184) $ — $ (59,184) $ — Long-term contingent consideration (188,500) — — (188,500) (189,600) — — (189,600) Other long-term liabilities: Foreign currency forward contracts (29) — (29) — (4,283) — (4,283) — Total financial liabilities $ (192,885) $ — $ (4,385) $ (188,500) $ (253,067) $ — $ (63,467) $ (189,600)
Schedule of Fair Value of Our Contingent Consideration Liabilities	The following table represents a rollforward of the fair value of the Company’s contingent consideration liabilities: Nine Months Ended September 30, 2021 (in thousands) Balance at December 31, 2020 $ 189,600 Decrease in fair value of contingent payments (1,100) Balance at September 30, 2021 $ 188,500

Marketable Securities and Equ_2

Marketable Securities and Equity Investments (Tables)	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Schedule of Cash Equivalents and Marketable Securities	A summary of the Company’s cash equivalents and marketable securities, which are recorded at fair value (and do not include $2.7 billion and $2.8 billion of cash as of September 30, 2021 and December 31, 2020, respectively), is shown below: As of September 30, 2021 As of December 31, 2020 Amortized Cost Gross Gross Fair Value Amortized Cost Gross Gross Fair Value (in thousands) Cash equivalents: Money market funds $ 3,578,764 $ — $ — $ 3,578,764 $ 3,141,053 $ — $ — $ 3,141,053 Commercial paper 31,997 1 — 31,998 — — — — Total cash equivalents $ 3,610,761 $ 1 $ — $ 3,610,762 $ 3,141,053 $ — $ — $ 3,141,053 Marketable securities: U.S. Treasury securities $ 46,536 $ 4 $ (1) $ 46,539 $ — $ — $ — $ — Government-sponsored enterprise securities 68,996 8 (2) 69,002 80,046 17 — 80,063 Corporate debt securities 95,385 26 (52) 95,359 231,263 377 (42) 231,598 Commercial paper 255,501 40 (18) 255,523 163,286 19 (37) 163,268 Total marketable debt securities 466,418 78 (73) 466,423 474,595 413 (79) 474,929 Corporate equity securities 69,418 150,263 (917) 218,764 51,427 144,354 — 195,781 Total marketable securities $ 535,836 $ 150,341 $ (990) $ 685,187 $ 526,022 $ 144,767 $ (79) $ 670,710 Available-for-sale debt securities were classified on the Company's condensed consolidated balance sheets at fair value as follows: As of September 30, 2021 As of December 31, 2020 (in thousands) Cash and cash equivalents $ 3,610,762 $ 3,141,053 Marketable securities 466,423 474,929 Total $ 4,077,185 $ 3,615,982 Available-for-sale debt securities by contractual maturity were as follows: As of September 30, 2021 As of December 31, 2020 (in thousands) Matures within one year $ 4,014,441 $ 3,526,185 Matures after one year through five years 62,744 89,797 Total $ 4,077,185 $ 3,615,982
Schedule of Company's Net Unrealized Gains on Corporate Equity Securities	During the three and nine months ended September 30, 2021 and 2020, the Company’s net unrealized gains on corporate equity securities held at the conclusion of each period were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Net unrealized gains $ 46,679 $ 69,834 $ 4,993 $ 102,317

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table summarizes the changes in accumulated other comprehensive income (loss) by component: Foreign Currency Translation Adjustment Unrealized Holding Gains (Losses), Net of Tax Total On Available-For-Sale Debt Securities On Foreign Currency Forward Contracts (in thousands) Balance at December 31, 2020 $ (15,678) $ 334 $ (53,136) $ (68,480) Other comprehensive income (loss) before reclassifications 3,335 (329) 46,175 49,181 Amounts reclassified from accumulated other comprehensive (loss) income — — 30,836 30,836 Net current period other comprehensive income (loss) 3,335 (329) 77,011 80,017 Balance at September 30, 2021 $ (12,343) $ 5 $ 23,875 $ 11,537 Balance at December 31, 2019 $ (895) $ 503 $ (1,581) $ (1,973) Other comprehensive (loss) income before reclassifications (12,616) 818 (20,913) (32,711) Amounts reclassified from accumulated other comprehensive loss — — (6,298) (6,298) Net current period other comprehensive (loss) income (12,616) 818 (27,211) (39,009) Balance at September 30, 2020 $ (13,511) $ 1,321 $ (28,792) $ (40,982)

Hedging (Tables)

Hedging (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Cash Flow Hedging Instruments	The following table summarizes the notional amount in U.S. dollars of the Company’s outstanding foreign currency forward contracts designated as cash flow hedges under U.S. GAAP: As of September 30, 2021 As of December 31, 2020 Foreign Currency (in thousands) Euro $ 1,194,338 $ 745,099 British pound sterling 277,815 160,427 Australian dollar 95,970 99,922 Canadian dollar 87,259 86,468 Swiss Franc 41,335 — Total foreign currency forward contracts $ 1,696,717 $ 1,091,916
Schedule of Foreign Exchange Contracts, Condensed Consolidated Statements of Operations	During the three and nine months ended September 30, 2021 and 2020, the Company recognized the following related to foreign currency forward contracts in its condensed consolidated statements of operations: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Designated as hedging instruments - Reclassified from AOCI Product revenues, net $ (5,224) $ (7,249) $ (39,342) $ 8,039 Not designated as hedging instruments Other income (expense), net $ (400) $ 25,897 $ (9,350) $ 15,724 Total reported in the Condensed Consolidated Statement of Operations Product revenues, net $ 1,984,164 $ 1,536,271 $ 5,500,839 $ 4,575,863 Other income (expense), net $ 42,368 $ 84,386 $ (2,234) $ 139,621
Schedule of Foreign Exchange Contracts	The following table summarizes the fair value of the Company’s outstanding foreign currency forward contracts designated as cash flow hedges under U.S. GAAP included on its condensed consolidated balance sheets: As of September 30, 2021 Assets Liabilities Classification Fair Value Classification Fair Value (in thousands) Prepaid expenses and other current assets $ 34,300 Other current liabilities $ (4,356) Other assets 4,781 Other long-term liabilities (29) Total assets $ 39,081 Total liabilities $ (4,385) As of December 31, 2020 Assets Liabilities Classification Fair Value Classification Fair Value (in thousands) Prepaid expenses and other current assets $ — Other current liabilities $ (59,184) Other assets — Other long-term liabilities (4,283) Total assets $ — Total liabilities $ (63,467)
Schedule of Offsetting Liabilities	The following table summarizes the potential effect of offsetting derivatives by type of financial instrument designated as cash flow hedges under U.S. GAAP on the Company’s condensed consolidated balance sheets: As of September 30, 2021 Gross Amounts Recognized Gross Amounts Offset Gross Amounts Presented Gross Amounts Not Offset Legal Offset Foreign currency forward contracts (in thousands) Total assets $ 39,081 $ — $ 39,081 $ (4,385) $ 34,696 Total liabilities (4,385) — (4,385) 4,385 — As of December 31, 2020 Gross Amounts Recognized Gross Amounts Offset Gross Amounts Presented Gross Amounts Not Offset Legal Offset Foreign currency forward contracts (in thousands) Total assets $ — $ — $ — $ — $ — Total liabilities (63,467) — (63,467) — (63,467)
Schedule of Offsetting Assets	The following table summarizes the potential effect of offsetting derivatives by type of financial instrument designated as cash flow hedges under U.S. GAAP on the Company’s condensed consolidated balance sheets: As of September 30, 2021 Gross Amounts Recognized Gross Amounts Offset Gross Amounts Presented Gross Amounts Not Offset Legal Offset Foreign currency forward contracts (in thousands) Total assets $ 39,081 $ — $ 39,081 $ (4,385) $ 34,696 Total liabilities (4,385) — (4,385) 4,385 — As of December 31, 2020 Gross Amounts Recognized Gross Amounts Offset Gross Amounts Presented Gross Amounts Not Offset Legal Offset Foreign currency forward contracts (in thousands) Total assets $ — $ — $ — $ — $ — Total liabilities (63,467) — (63,467) — (63,467)

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Schedule of Inventories by Type	Inventories consisted of the following: As of September 30, 2021 As of December 31, 2020 (in thousands) Raw materials $ 45,990 $ 46,232 Work-in-process 192,650 161,324 Finished goods 94,816 73,221 Total $ 333,456 $ 280,777

Stock-based Compensation Expe_2

Stock-based Compensation Expense and Share Repurchase Programs (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Stock-based Compensation Expense by Line Item	During the three and nine months ended September 30, 2021 and 2020, the Company recognized the following stock-based compensation expense: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands) Stock-based compensation expense by type of award: Restricted stock units (including PSUs) and restricted stock $ 89,458 $ 84,043 $ 279,131 $ 279,611 Stock options 7,875 13,221 29,580 47,334 ESPP share issuances 6,321 3,225 17,895 8,565 Stock-based compensation expense related to inventories (658) (950) (3,814) (3,076) Total stock-based compensation expense included in costs and expenses $ 102,996 $ 99,539 $ 322,792 $ 332,434 Stock-based compensation expense by line item: Cost of sales $ 1,599 $ 1,250 $ 4,570 $ 3,998 Research and development expenses 60,995 60,770 196,412 203,732 Selling, general and administrative expenses 40,402 37,519 121,810 124,704 Total stock-based compensation expense included in costs and expenses 102,996 99,539 322,792 332,434 Income tax effect (21,556) (35,295) (73,663) (130,692) Total stock-based compensation expense, net of tax $ 81,440 $ 64,244 $ 249,129 $ 201,742

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Schedule of Provision for Income Taxes and Effective Tax rates	During the three and nine months ended September 30, 2021 and 2020, the Company recorded the following provisions for income taxes and effective tax rates as compared to its income before provision for income taxes: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (in thousands, except percentages) Income before provision for income taxes $ 1,082,741 $ 745,871 $ 1,859,446 $ 2,228,175 Provision for income taxes 230,813 78,437 287,456 120,718 Effective tax rate 21 % 11 % 15 % 5 %

Additional Cash Flow Informat_2

Additional Cash Flow Information (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Condensed Cash Flow Statement	The cash, cash equivalents and restricted cash at the beginning and ending of each period presented in the Company’s condensed consolidated statements of cash flows consisted of the following: Nine Months Ended September 30, 2021 2020 Beginning of period End of period Beginning of period End of period (in thousands) Cash and cash equivalents $ 5,988,187 $ 6,275,698 $ 3,109,322 $ 5,358,087 Prepaid expenses and other current assets 658 4,515 8,004 2,898 Other assets — — 3,355 — Cash, cash equivalents and restricted cash per condensed consolidated statement of cash flows $ 5,988,845 $ 6,280,213 $ 3,120,681 $ 5,360,985

Basis of Presentation and Acc_3

Basis of Presentation and Accounting Policies (Details)	9 Months Ended
	Sep. 30, 2021segment
Accounting Policies [Abstract]
Number of operating segments	1

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 1,984,164	$ 1,538,271	$ 5,501,839	$ 4,577,863
United States
Disaggregation of Revenue [Line Items]
Revenues	1,382,892	1,222,565	3,893,245	3,620,467
Europe
Disaggregation of Revenue [Line Items]
Revenues	518,826	251,366	1,382,701	766,438
Other
Disaggregation of Revenue [Line Items]
Revenues	82,446	62,340	224,893	188,958
Total product revenues outside of the United States
Disaggregation of Revenue [Line Items]
Revenues	601,272	313,706	1,607,594	955,396
Product revenues, net
Disaggregation of Revenue [Line Items]
Revenues	1,984,164	1,536,271	5,500,839	4,575,863
TRIKAFTA/KAFTRIO
Disaggregation of Revenue [Line Items]
Revenues	1,555,772	960,308	4,004,600	2,773,256
SYMDEKO/SYMKEVI
Disaggregation of Revenue [Line Items]
Revenues	81,415	156,178	339,969	501,066
ORKAMBI
Disaggregation of Revenue [Line Items]
Revenues	184,561	225,919	624,224	692,038
KALYDECO
Disaggregation of Revenue [Line Items]
Revenues	$ 162,416	$ 193,866	$ 532,046	$ 609,503

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Contract liabilities	$ 104.1	$ 191.5

Collaborative Arrangements - Ad

Collaborative Arrangements - Additional Information (Details)	1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Jun. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Dec. 31, 2019USD ($)target	Jul. 01, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, research and development expenses		$ 26,800,000			$ 986,800,000
Up-front payment				$ 80,100,000		$ 143,300,000
CRISPR Therapeutics
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, right to exclusively license, number of targets | target							3
Collaborative arrangement, development and regulatory potential milestone payments maximum							$ 410,000,000
CRISPR A&R JDCA
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Up-front payment			$ 900,000,000
Collaborative arrangement, development and regulatory potential milestone payments maximum			$ 200,000,000
Allocation of net profits and net losses, percent								60.00%
CRISPR A&R JDCA | CRISPR
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Allocation of net profits and net losses, percent								40.00%
Moderna, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Up-front payment	$ 75,000,000
Collaborative arrangement, development and regulatory potential milestone payments maximum	$ 380,000,000

Collaborative Arrangements - Co

Collaborative Arrangements - Collaborative Arrangement on Research and Development (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, research and development expenses	$ 493,751	$ 493,497	$ 2,356,814	$ 1,362,953
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | CRISPR Therapeutics
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, research and development expenses	58,659	28,623	147,448	66,720
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | CRISPR Therapeutics | Research and development expenses
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, research and development expenses	$ 35,195	$ 14,311	$ 79,590	$ 33,360

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Computation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share
Net income	$ 851,928	$ 667,434	$ 1,571,990	$ 2,107,457
Basic weighted-average common shares outstanding (in shares)	257,876	260,392	258,740	260,313
Effect of potentially dilutive securities:
Employee stock purchase program (in shares)	19	12	10	17
Diluted weighted-average common shares outstanding (in shares)	259,707	264,079	260,877	264,031
Basic net income per common share (in dollars per share)	$ 3.30	$ 2.56	$ 6.08	$ 8.10
Diluted net income per common share (in dollars per share)	$ 3.28	$ 2.53	$ 6.03	$ 7.98
Stock options
Effect of potentially dilutive securities:
Share-based payment arrangements (in shares)	971	1,887	1,124	1,936
Restricted stock units (including PSUs)
Effect of potentially dilutive securities:
Share-based payment arrangements (in shares)	841	1,788	1,003	1,765

Earnings Per Share - Anti-dilut

Earnings Per Share - Anti-dilutive Securities (Details) - shares shares in Thousands	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
Antidilutive securities excluded from computation of earnings per share (in shares)	1,060	23	711	303
Restricted stock units (including PSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from computation of earnings per share (in shares)	204	252	440	229

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) $ in Millions	Sep. 30, 2021USD ($)	Dec. 31, 2020USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash	$ 2,700	$ 2,800
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Remaining milestone payment	$ 678.3
Level 3 | Minimum | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration, measurement input (as a percent)	0.003
Level 3 | Maximum | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration, measurement input (as a percent)	0.022

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Subject to Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financial instruments carried at fair value (liability positions):
Long-term contingent consideration	$ (188,500)	$ (189,600)
Recurring Basis
Financial instruments carried at fair value (asset positions):
Derivative asset current, foreign currency forward contracts	34,300	0
Derivative asset noncurrent, foreign currency forward contracts	4,781	0
Total financial assets	4,335,030	3,811,763
Financial instruments carried at fair value (liability positions):
Derivative liability current, foreign currency forward contracts	(4,356)	(59,184)
Long-term contingent consideration	(188,500)	(189,600)
Derivative liability noncurrent, foreign currency forward contracts	(29)	(4,283)
Total financial liabilities	(192,885)	(253,067)
Recurring Basis | Level 1
Financial instruments carried at fair value (asset positions):
Derivative asset current, foreign currency forward contracts	0	0
Derivative asset noncurrent, foreign currency forward contracts	0	0
Total financial assets	3,913,069	3,236,766
Financial instruments carried at fair value (liability positions):
Derivative liability current, foreign currency forward contracts	0	0
Long-term contingent consideration	0	0
Derivative liability noncurrent, foreign currency forward contracts	0	0
Total financial liabilities	0	0
Recurring Basis | Level 2
Financial instruments carried at fair value (asset positions):
Derivative asset current, foreign currency forward contracts	34,300	0
Derivative asset noncurrent, foreign currency forward contracts	4,781	0
Total financial assets	421,961	574,997
Financial instruments carried at fair value (liability positions):
Derivative liability current, foreign currency forward contracts	(4,356)	(59,184)
Long-term contingent consideration	0	0
Derivative liability noncurrent, foreign currency forward contracts	(29)	(4,283)
Total financial liabilities	(4,385)	(63,467)
Recurring Basis | Level 3
Financial instruments carried at fair value (asset positions):
Derivative asset current, foreign currency forward contracts	0	0
Derivative asset noncurrent, foreign currency forward contracts	0	0
Total financial assets	0	0
Financial instruments carried at fair value (liability positions):
Derivative liability current, foreign currency forward contracts	0	0
Long-term contingent consideration	(188,500)	(189,600)
Derivative liability noncurrent, foreign currency forward contracts	0	0
Total financial liabilities	(188,500)	(189,600)
Recurring Basis | Money market funds
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	3,578,764	3,141,053
Recurring Basis | Money market funds | Level 1
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	3,578,764	3,141,053
Recurring Basis | Money market funds | Level 2
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	0	0
Recurring Basis | Money market funds | Level 3
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	0	0
Recurring Basis | Commercial paper
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	31,998	0
Marketable securities	255,523	163,268
Recurring Basis | Commercial paper | Level 1
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	0	0
Marketable securities	0	0
Recurring Basis | Commercial paper | Level 2
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	31,998	0
Marketable securities	255,523	163,268
Recurring Basis | Commercial paper | Level 3
Financial instruments carried at fair value (asset positions):
Cash and cash equivalents	0	0
Marketable securities	0	0
Recurring Basis | Corporate equity securities
Financial instruments carried at fair value (asset positions):
Marketable securities	218,764	195,781
Recurring Basis | Corporate equity securities | Level 1
Financial instruments carried at fair value (asset positions):
Marketable securities	218,764	15,650
Recurring Basis | Corporate equity securities | Level 2
Financial instruments carried at fair value (asset positions):
Marketable securities	0	180,131
Recurring Basis | Corporate equity securities | Level 3
Financial instruments carried at fair value (asset positions):
Marketable securities	0	0
Recurring Basis | U.S. Treasury securities
Financial instruments carried at fair value (asset positions):
Marketable securities	46,539	0
Recurring Basis | U.S. Treasury securities | Level 1
Financial instruments carried at fair value (asset positions):
Marketable securities	46,539	0
Recurring Basis | U.S. Treasury securities | Level 2
Financial instruments carried at fair value (asset positions):
Marketable securities	0	0
Recurring Basis | U.S. Treasury securities | Level 3
Financial instruments carried at fair value (asset positions):
Marketable securities	0	0
Recurring Basis | Government-sponsored enterprise securities
Financial instruments carried at fair value (asset positions):
Marketable securities	69,002	80,063
Recurring Basis | Government-sponsored enterprise securities | Level 1
Financial instruments carried at fair value (asset positions):
Marketable securities	69,002	80,063
Recurring Basis | Government-sponsored enterprise securities | Level 2
Financial instruments carried at fair value (asset positions):
Marketable securities	0	0
Recurring Basis | Government-sponsored enterprise securities | Level 3
Financial instruments carried at fair value (asset positions):
Marketable securities	0	0
Recurring Basis | Corporate debt securities
Financial instruments carried at fair value (asset positions):
Marketable securities	95,359	231,598
Recurring Basis | Corporate debt securities | Level 1
Financial instruments carried at fair value (asset positions):
Marketable securities	0	0
Recurring Basis | Corporate debt securities | Level 2
Financial instruments carried at fair value (asset positions):
Marketable securities	95,359	231,598
Recurring Basis | Corporate debt securities | Level 3
Financial instruments carried at fair value (asset positions):
Marketable securities	$ 0	$ 0

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value of Contingent Consideration Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at December 31, 2020			$ 189,600
Decrease in fair value of contingent payments	$ 1,200	$ 1,800	(1,100)	$ 12,600
Balance at September 30, 2021	$ 188,500		$ 188,500

Marketable Securities and Equ_3

Marketable Securities and Equity Investments - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Summary of cash, cash equivalents and marketable securities
Cash	$ 2,700,000,000		$ 2,700,000,000		$ 2,800,000,000
Other-than-temporary declines in fair value of available-for-sale debt securities	0	$ 0	0	$ 0
Net unrealized gains	46,679,000	69,834,000	4,993,000	102,317,000
Weighted-average cost basis	69,418,000	$ 51,300,000	69,418,000	51,300,000	$ 51,427,000
Other Assets
Summary of cash, cash equivalents and marketable securities
Equity securities without readily determinable fair value, amount	$ 35,900,000		35,900,000
Publicly Traded Companies Sale
Summary of cash, cash equivalents and marketable securities
Proceeds received			$ 0	$ 149,600,000

Marketable Securities and Equ_4

Marketable Securities and Equity Investments - Summary of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Total marketable debt securities
Fair Value	$ 4,077,185	$ 3,615,982
Corporate equity securities
Amortized Cost	69,418	51,427	$ 51,300
Gross Unrealized Gains	150,263	144,354
Gross Unrealized Losses	(917)	0
Fair Value	218,764	195,781
Amortized Cost	535,836	526,022
Gross Unrealized Gains	150,341	144,767
Gross Unrealized Losses	(990)	(79)
Fair Value	685,187	670,710
Cash equivalents:
Total marketable debt securities
Amortized Cost	3,610,761	3,141,053
Gross Unrealized Gains	1	0
Gross Unrealized Losses	0	0
Fair Value	3,610,762	3,141,053
Cash equivalents: | Money market funds
Total marketable debt securities
Amortized Cost	3,578,764	3,141,053
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	3,578,764	3,141,053
Cash equivalents: | Commercial paper
Total marketable debt securities
Amortized Cost	31,997	0
Gross Unrealized Gains	1	0
Gross Unrealized Losses	0	0
Fair Value	31,998	0
Marketable securities
Total marketable debt securities
Amortized Cost	466,418	474,595
Gross Unrealized Gains	78	413
Gross Unrealized Losses	(73)	(79)
Fair Value	466,423	474,929
Marketable securities | U.S. Treasury securities
Total marketable debt securities
Amortized Cost	46,536	0
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(1)	0
Fair Value	46,539	0
Marketable securities | Government-sponsored enterprise securities
Total marketable debt securities
Amortized Cost	68,996	80,046
Gross Unrealized Gains	8	17
Gross Unrealized Losses	(2)	0
Fair Value	69,002	80,063
Marketable securities | Corporate debt securities
Total marketable debt securities
Amortized Cost	95,385	231,263
Gross Unrealized Gains	26	377
Gross Unrealized Losses	(52)	(42)
Fair Value	95,359	231,598
Marketable securities | Commercial paper
Total marketable debt securities
Amortized Cost	255,501	163,286
Gross Unrealized Gains	40	19
Gross Unrealized Losses	(18)	(37)
Fair Value	$ 255,523	$ 163,268

Marketable Securities and Equ_5

Marketable Securities and Equity Investments - Available-for-Sale Debt Securities at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Debt securities	$ 4,077,185	$ 3,615,982
Cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Debt securities	3,610,762	3,141,053
Marketable securities
Debt Securities, Available-for-sale [Line Items]
Debt securities	$ 466,423	$ 474,929

Marketable Securities and Equ_6

Marketable Securities and Equity Investments - Available-for-Sale Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Matures within one year	$ 4,014,441	$ 3,526,185
Matures after one year through five years	62,744	89,797
Total	$ 4,077,185	$ 3,615,982

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 9,196,396	$ 7,519,242	$ 8,686,815	$ 6,085,244
Other comprehensive income (loss) before reclassifications			49,181	(32,711)
Amounts reclassified from accumulated other comprehensive (loss) income			30,836	(6,298)
Total other comprehensive income (loss)	36,696	(26,861)	80,017	(39,009)
Ending balance	9,530,708	8,133,473	9,530,708	8,133,473
Foreign Currency Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(15,678)	(895)
Other comprehensive income (loss) before reclassifications			3,335	(12,616)
Amounts reclassified from accumulated other comprehensive (loss) income			0	0
Total other comprehensive income (loss)			3,335	(12,616)
Ending balance	(12,343)	(13,511)	(12,343)	(13,511)
Unrealized Holding Gains (Losses), Net of Tax On Available-For-Sale Debt Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			334	503
Other comprehensive income (loss) before reclassifications			(329)	818
Amounts reclassified from accumulated other comprehensive (loss) income			0	0
Total other comprehensive income (loss)			(329)	818
Ending balance	5	1,321	5	1,321
Unrealized Holding Gains (Losses), Net of Tax On Foreign Currency Foreign Forward Contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(53,136)	(1,581)
Other comprehensive income (loss) before reclassifications			46,175	(20,913)
Amounts reclassified from accumulated other comprehensive (loss) income			30,836	(6,298)
Total other comprehensive income (loss)			77,011	(27,211)
Ending balance	23,875	(28,792)	23,875	(28,792)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(25,159)	(14,121)	(68,480)	(1,973)
Total other comprehensive income (loss)	36,696	(26,861)	80,017	(39,009)
Ending balance	$ 11,537	$ (40,982)	$ 11,537	$ (40,982)

Hedging - Additional Informatio

Hedging - Additional Information (Details) - Foreign Currency Forward Contracts	9 Months Ended
	Sep. 30, 2021USD ($)
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative term	1 month
Cash Flow Hedging | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount of foreign currency forward contract	$ 306,200,000
Cash Flow Hedging | Minimum
Derivative [Line Items]
Derivative term	1 month
Cash Flow Hedging | Maximum
Derivative [Line Items]
Derivative term	18 months

Hedging - Notional Amount (Deta

Hedging - Notional Amount (Details) - Foreign Currency Forward Contracts - Designated as Hedging Instruments - Cash Flow Hedging - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Notional amount of foreign currency forward contract	$ 1,696,717	$ 1,091,916
Euro
Derivative [Line Items]
Notional amount of foreign currency forward contract	1,194,338	745,099
British pound sterling
Derivative [Line Items]
Notional amount of foreign currency forward contract	277,815	160,427
Australian dollar
Derivative [Line Items]
Notional amount of foreign currency forward contract	95,970	99,922
Canadian dollar
Derivative [Line Items]
Notional amount of foreign currency forward contract	87,259	86,468
Swiss Franc
Derivative [Line Items]
Notional amount of foreign currency forward contract	$ 41,335	$ 0

Hedging - Cash Flow Hedging Ins

Hedging - Cash Flow Hedging Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Revenues	$ 1,984,164	$ 1,538,271	$ 5,501,839	$ 4,577,863
Other income (expense), net	42,368	84,386	(2,234)	139,621
Foreign Currency Forward Contract | Reclassification out of Accumulated Other Comprehensive Income | Foreign Currency Forward Contracts | Not designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Other income (expense), net	(400)	25,897	(9,350)	15,724
Product revenues, net
Derivative Instruments, Gain (Loss) [Line Items]
Revenues	1,984,164	1,536,271	5,500,839	4,575,863
Product revenues, net | Foreign Currency Forward Contract | Reclassification out of Accumulated Other Comprehensive Income | Foreign Currency Forward Contracts | Designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Revenues	$ (5,224)	$ (7,249)	$ (39,342)	$ 8,039

Hedging - Derivative Fair Value

Hedging - Derivative Fair Value (Details) - Designated as Hedging Instruments - Foreign Currency Forward Contracts - Cash Flow Hedging - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Total assets	$ 39,081	$ 0
Total liabilities	(4,385)	(63,467)
Prepaid expenses and other current assets
Derivative [Line Items]
Total assets	34,300	0
Other assets
Derivative [Line Items]
Total assets	4,781	0
Other current liabilities
Derivative [Line Items]
Total liabilities	(4,356)	(59,184)
Other long-term liabilities
Derivative [Line Items]
Total liabilities	$ (29)	$ (4,283)

Hedging - Offsetting Derivative

Hedging - Offsetting Derivatives (Details) - Cash Flow Hedging - Designated as Hedging Instruments - Foreign Currency Forward Contracts - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Offsetting Derivative Assets [Abstract]
Gross Amounts Recognized	$ 39,081	$ 0
Gross Amounts Offset	0	0
Gross Amounts Presented	39,081	0
Gross Amounts Not Offset	(4,385)	0
Legal Offset	34,696	0
Offsetting Derivative Liabilities [Abstract]
Gross Amounts Recognized	(4,385)	(63,467)
Gross Amounts Offset	0	0
Gross Amounts Presented	(4,385)	(63,467)
Gross Amounts Not Offset	4,385	0
Legal Offset	$ 0	$ (63,467)

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 45,990	$ 46,232
Work-in-process	192,650	161,324
Finished goods	94,816	73,221
Total	$ 333,456	$ 280,777

Stock-based Compensation Expe_3

Stock-based Compensation Expense and Share Repurchase Programs - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock-based compensation expense:
Total stock-based compensation expense included in costs and expenses	$ 102,996	$ 99,539	$ 322,792	$ 332,434
Stock-based compensation expense related to inventories	(658)	(950)	(3,814)	(3,076)
Total stock-based compensation expense included in costs and expenses	102,996	99,539	322,792	332,434
Income tax effect	(21,556)	(35,295)	(73,663)	(130,692)
Total stock-based compensation expense, net of tax	81,440	64,244	249,129	201,742
Cost of sales
Stock-based compensation expense:
Total stock-based compensation expense included in costs and expenses	1,599	1,250	4,570	3,998
Research and development expenses
Stock-based compensation expense:
Total stock-based compensation expense included in costs and expenses	60,995	60,770	196,412	203,732
Selling, general and administrative expenses
Stock-based compensation expense:
Total stock-based compensation expense included in costs and expenses	40,402	37,519	121,810	124,704
Restricted stock units (including PSUs)
Stock-based compensation expense:
Total stock-based compensation expense included in costs and expenses	89,458	84,043	279,131	279,611
Stock options
Stock-based compensation expense:
Total stock-based compensation expense included in costs and expenses	7,875	13,221	29,580	47,334
ESPP share issuances
Stock-based compensation expense:
Total stock-based compensation expense included in costs and expenses	$ 6,321	$ 3,225	$ 17,895	$ 8,565

Stock-based Compensation Expe_4

Stock-based Compensation Expense and Share Repurchase Programs - Additional Information (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 23, 2021	Dec. 31, 2020	Nov. 30, 2020	Dec. 31, 2019
Equity, Class of Treasury Stock [Line Items]
Amount of shares repurchased	$ 642,273,000		$ 108,007,000	$ 1,067,225,000	$ 408,033,000
Share Repurchase Program 2019
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized to be repurchased							$ 500,000,000		$ 500,000,000
Shares repurchased (in shares)					1,806,587
Amount of shares repurchased					$ 408,000,000
Share Repurchase Program 2020
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized to be repurchased								$ 500,000,000
Shares repurchased (in shares)		1,988,941
Amount of shares repurchased		$ 424,900,000
Share Repurchase Program 2021
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized to be repurchased						$ 1,500,000,000
Shares repurchased (in shares)	3,293,161
Amount of shares repurchased	$ 642,200,000
Stock repurchase program, remaining amount	$ 857,800,000			$ 857,800,000

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Tax Contingency [Line Items]
Income before provision for income taxes	$ 1,082,741	$ 745,871	$ 1,859,446	$ 2,228,175
Provision for income taxes	$ 230,813	$ 78,437	$ 287,456	$ 120,718
Effective tax rate	21.00%	11.00%	15.00%	5.00%
Discrete tax benefit associated with intra-entity transfer of intellectual property rights				$ 209,000
Net unrecognized tax benefits which would affect the tax rate if recognized	$ 89,000		$ 89,000		$ 75,800
UK Corporate Tax Rate
Income Tax Contingency [Line Items]
Discrete tax benefit associated with an increase in the U.K. corporate tax rate			$ 99,700

Commitments and Contingencies (

Commitments and Contingencies (Details)	1 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2021USD ($)credit_agreement	Dec. 31, 2020USD ($)
Line of Credit Facility [Line Items]
Number of credit agreements | credit_agreement			2
Indemnification claims			$ 0
Contingent liabilities			$ 0	$ 0
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 2,000,000,000	$ 500,000,000
Line of credit facility additional borrowing capacity	$ 500,000,000
Debt covenant, consolidated leverage ratio	3.50
Debt covenant, increase in consolidated leverage ratio	4
Debt covenant, interest coverage ratio	2.50
Revolving Credit Facility | Base Rate | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	0.50%	0.125%
Revolving Credit Facility | Base Rate | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	0.875%	0.50%
Revolving Credit Facility | Eurodollar | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	1.50%	1.125%
Revolving Credit Facility | Eurodollar | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	1.875%	1.50%
Letters of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 50,000,000

Additional Cash Flow Informat_3

Additional Cash Flow Information (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 6,275,698	$ 5,988,187	$ 5,358,087	$ 3,109,322
Cash, cash equivalents and restricted cash per condensed consolidated statement of cash flows	6,280,213	5,988,845	5,360,985	3,120,681
Prepaid expenses and other current assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents	4,515	658	2,898	8,004
Other assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents	$ 0	$ 0	$ 0	$ 3,355