Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis and Level of Inputs used in such Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents, Adjusted Cost	$ 105,585	$ 68,525	$ 55,046
Fair Value Measurements Recurring
Assets
Assets, Adjusted Cost	287,279	203,268
Assets, Unrealized Gains		32
Assets, Unrealized Losses	(215)	(10)
Assets, Fair Value	287,064	203,290
Cash and cash equivalents, Adjusted Cost	105,587	68,526
Cash and cash equivalents, Unrealized Losses	(2)	(1)
Cash and cash equivalents, Fair Value	105,585	68,525
Fair Value Measurements Recurring \| Short-term Investments
Assets
Investments, Adjusted Cost	181,692	134,742
Investments, Unrealized Gains		32
Investments, Unrealized Losses	(213)	(9)
Investments, Fair Value	181,479	134,765
Fair Value Measurements Recurring \| Commercial Paper \| Level 2
Assets
Cash and cash equivalents, Adjusted Cost	50,005	41,145
Cash and cash equivalents, Unrealized Losses	(2)	(1)
Cash and cash equivalents, Fair Value	50,003	41,144
Fair Value Measurements Recurring \| Commercial Paper \| Level 2 \| Short-term Investments
Assets
Investments, Adjusted Cost	18,068	25,470
Investments, Unrealized Losses	(2)
Investments, Fair Value	18,066	25,470
Fair Value Measurements Recurring \| U.S. Government Securities \| Level 2 \| Short-term Investments
Assets
Investments, Adjusted Cost	50,040	18,260
Investments, Unrealized Gains		1
Investments, Unrealized Losses	(15)
Investments, Fair Value	50,025	18,261
Fair Value Measurements Recurring \| Corporate Debt Securities \| Level 2 \| Short-term Investments
Assets
Investments, Adjusted Cost	18,059	29,576
Investments, Unrealized Losses	(7)	(8)
Investments, Fair Value	18,052	29,568
Fair Value Measurements Recurring \| U.S. Agency Securities \| Level 2 \| Short-term Investments
Assets
Investments, Adjusted Cost	19,738	61,436
Investments, Unrealized Gains		31
Investments, Unrealized Losses	(35)	(1)
Investments, Fair Value	19,703	61,466
Fair Value Measurements Recurring \| Asset-backed Securities \| Level 2 \| Short-term Investments
Assets
Investments, Adjusted Cost	75,787
Investments, Unrealized Losses	(154)
Investments, Fair Value	75,633
Fair Value Measurements Recurring \| Cash
Assets
Cash and cash equivalents, Adjusted Cost	6,094	4,767
Cash and cash equivalents, Fair Value	6,094	4,767
Fair Value Measurements Recurring \| Money Market Funds \| Level 1
Assets
Cash and cash equivalents, Adjusted Cost	49,488	22,614
Cash and cash equivalents, Fair Value	$ 49,488	$ 22,614

Assets, amortized cost basis.

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Assets, gross unrealized gains.

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Assets, gross unrealized losses.

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Cash and cash equivalents, gross unrealized losses.

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

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

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