Acquisitions, Divestitures and Other Arrangements - Schedule of Total Consideration for the Acquisitions (Detail) - Viela Bio [Member] - USD ($) $ in Thousands		3 Months Ended
Mar. 15, 2021	Mar. 31, 2022
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Equity value (54,988,820 shares at $53.00 per share)		$ 2,914,407
Net settlements on the exercise of stock options		78,554
Consideration for exchange of Viela stock options		1,130
Total consideration	$ 3,000,000	$ 2,994,091

Business Combination, net settlements on the exercise of stock options.

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- Definition

Consideration for exchange of stock options.

+ References

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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