Fair Value of Financial Instruments - Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	$ 36,380	$ 152,974
Unrealized Losses	(2,229)	(588)
Estimated Fair Value	551,320	490,967
Amortized Cost	589,930	644,529
Estimated Fair Value	587,701	643,941
Cash equivalents: \| Money market funds
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	36,380	102,978
Cash equivalents: \| U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Cash equivalents		49,996
Short-term investments: \| U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	467,564	330,618
Unrealized Losses	(2,194)	(565)
Estimated Fair Value	465,370	330,053
Short-term investments: \| Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	85,986	160,937
Unrealized Losses	(35)	(23)
Estimated Fair Value	$ 85,951	$ 160,914

Cash And Cash Equivalents, At Carrying Value and Debt Securities, Available For Sale

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- Definition

Cash And Cash Equivalents, At Carrying Value and Debt Securities Available For Sale, Amortized Cost

+ References

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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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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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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.

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