Fair Value - Schedule of Fair Value of Cash Equivalents, Short-term Investments and Long-term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	$ 127,823	$ 60,625
Recurring Basis \| Cash Equivalents
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	118,378	53,772
Cash equivalents, Unrealized Losses	(3)	(2)
Cash equivalents, Fair Value	118,375	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	54,549	5
Cash equivalents, Fair Value	54,549	5
Recurring Basis \| Cash Equivalents \| Commercial Paper \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	63,829	44,318
Cash equivalents, Unrealized Losses	(3)	(2)
Cash equivalents, Fair Value	63,826	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	176,367	124,056
Investments, Unrealized Gains	21	8
Investments, Unrealized Losses	(21)	(7)
Investments, Fair Value	176,367	124,057
Recurring Basis \| Short-term Investments \| Commercial Paper \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	116,581	77,272
Investments, Unrealized Gains		1
Investments, Unrealized Losses	(15)	(4)
Investments, Fair Value	116,566	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	49,258	31,835
Investments, Unrealized Gains	21	7
Investments, Fair Value	49,279	31,842
Recurring Basis \| Short-term Investments \| Corporate Bonds \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	10,528	920
Investments, Unrealized Losses	(6)
Investments, Fair Value	10,522	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	53,436	83,475
Investments, Unrealized Gains	31	34
Investments, Fair Value	53,467	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	53,436	78,924
Investments, Unrealized Gains	31	32
Investments, Fair Value	$ 53,467	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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