Cash Equivalents and Marketable Securities - Schedule of Cash Equivalent and Marketable Securities Classified as Available-for-Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis Cash Equivalents	$ 257,318	$ 233,103
Unrealized Losses	(25)	(2)
Cash Equivalents, Estimated Fair Value	257,293	233,101
Amortized Cost Basis	476,186	626,976
Unrealized Gains	1	2
Unrealized Losses	(428)	(134)
Estimated Fair Value	475,759	626,844
Commercial Paper
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis Cash Equivalents	122,812	56,988
Unrealized Losses	(21)	(2)
Cash Equivalents, Estimated Fair Value	122,791	56,986
Agency Discount Notes
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis Cash Equivalents	34,937
Unrealized Losses	(4)
Cash Equivalents, Estimated Fair Value	34,933
Money Market Funds
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis Cash Equivalents	99,569	176,115
Cash Equivalents, Estimated Fair Value	99,569	176,115
Marketable Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	218,868	393,873
Unrealized Gains	1	2
Unrealized Losses	(403)	(132)
Estimated Fair Value	218,466	393,743
Marketable Securities \| U.S. Treasury Notes
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	76,127	76,518
Unrealized Losses	(151)	(46)
Estimated Fair Value	75,976	76,472
Marketable Securities \| Commercial Paper
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	126,709	167,761
Unrealized Gains	1	2
Unrealized Losses	(207)	(26)
Estimated Fair Value	126,503	167,737
Marketable Securities \| Corporate Debt Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis	16,032	122,548
Unrealized Losses	(45)	(58)
Estimated Fair Value	$ 15,987	122,490
Marketable Securities \| Supranational Debt Securities
Cash And Cash Equivalents [Line Items]
Amortized Cost Basis		27,046
Unrealized Losses		(2)
Estimated Fair Value		$ 27,044

Cash Equivalents Unrealized Losses

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Amount of 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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