Fair Value - Schedule of Fair Value of Cash Equivalents, Short-term Investments and Long-term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	$ 131,701	$ 60,625
Recurring Basis \| Cash Equivalents
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	120,417	53,772
Cash equivalents, Unrealized Losses		(2)
Cash equivalents, Fair Value	120,417	53,770
Recurring Basis \| Cash Equivalents \| Money Market Fund \| Level 1
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	119,417	5
Cash equivalents, Fair Value	119,417	5
Recurring Basis \| Cash Equivalents \| Commercial Paper \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	1,000	44,318
Cash equivalents, Unrealized Losses		(2)
Cash equivalents, Fair Value	1,000	44,316
Recurring Basis \| Cash Equivalents \| U.S. Government Debt and Agency Securities \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost		4,999
Cash equivalents, Fair Value		4,999
Recurring Basis \| Cash Equivalents \| U.S. Treasury Bills \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost		4,450
Cash equivalents, Fair Value		4,450
Recurring Basis \| Short-term Investments
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	153,218	124,056
Investments, Unrealized Gains	27	8
Investments, Unrealized Losses	(6)	(7)
Investments, Fair Value	153,239	124,057
Recurring Basis \| Short-term Investments \| Commercial Paper \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	103,680	77,272
Investments, Unrealized Gains	12	1
Investments, Unrealized Losses	(4)	(4)
Investments, Fair Value	103,688	77,269
Recurring Basis \| Short-term Investments \| U.S. Government Debt and Agency Securities \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	39,534	31,835
Investments, Unrealized Gains	15	7
Investments, Fair Value	39,549	31,842
Recurring Basis \| Short-term Investments \| Corporate Bonds \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	10,004	920
Investments, Unrealized Losses	(2)
Investments, Fair Value	10,002	920
Recurring Basis \| Short-term Investments \| U.S. Treasury Bills \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost		14,029
Investments, Unrealized Losses		(3)
Investments, Fair Value		14,026
Recurring Basis \| Long Term Investments
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	64,923	83,475
Investments, Unrealized Gains	18	34
Investments, Unrealized Losses	(2)
Investments, Fair Value	64,939	83,509
Recurring Basis \| Long Term Investments \| U.S. Government Debt and Agency Securities \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	64,923	78,924
Investments, Unrealized Gains	18	32
Investments, Unrealized Losses	(2)
Investments, Fair Value	$ 64,939	78,956
Recurring Basis \| Long Term Investments \| U.S. Treasury Bills \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost		4,551
Investments, Unrealized Gains		2
Investments, Fair Value		$ 4,553

Cash and cash equivalents accumulated gross unrealized loss before tax.

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- Definition

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), classified as current.

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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), classified as noncurrent.

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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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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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