Fair Value Measurements - Summary of Financial Assets Recognized at Fair Value on Recurring Basis (Detail) - Fair Value on Recurring Basis [Member] - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Assets
Cash equivalents and restricted cash equivalents	$ 139,471	$ 124,636
Marketable securities:
Marketable securities	707,533	962,643
Total Assets	847,004	1,087,279
Liabilities
Liabilities measured at fair value	18,600
Contingent Consideration Liability - research [Member]
Liabilities
Liabilities measured at fair value	18,600
U.S. Treasury and Other Government Securities [Member]
Marketable securities:
Marketable securities	291,527	300,477
Financial Institution Debt Securities [Member]
Marketable securities:
Marketable securities	325,263	440,416
Corporate Debt Securities [Member]
Marketable securities:
Marketable securities	66,246	62,349
Other Asset Backed Securities [Member]
Marketable securities:
Marketable securities	24,497	159,401
Level 1 [Member]
Assets
Cash equivalents and restricted cash equivalents	139,471	124,636
Marketable securities:
Marketable securities	276,621	280,085
Total Assets	416,092	404,721
Level 1 [Member] \| U.S. Treasury and Other Government Securities [Member]
Marketable securities:
Marketable securities	276,621
Total Assets		280,085
Level 2 [Member]
Marketable securities:
Marketable securities	430,912	682,558
Total Assets	430,912	682,558
Level 2 [Member] \| U.S. Treasury and Other Government Securities [Member]
Marketable securities:
Marketable securities	14,906	20,392
Level 2 [Member] \| Financial Institution Debt Securities [Member]
Marketable securities:
Marketable securities	325,263	440,416
Level 2 [Member] \| Corporate Debt Securities [Member]
Marketable securities:
Marketable securities	66,246	62,349
Level 2 [Member] \| Other Asset Backed Securities [Member]
Marketable securities:
Marketable securities	24,497	$ 159,401
Level 3 [Member]
Liabilities
Liabilities measured at fair value	18,600
Level 3 [Member] \| Contingent Consideration Liability - research [Member]
Liabilities
Liabilities measured at fair value	$ 18,600

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Fair value of financial and nonfinancial obligations.

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