Financial Instruments - Summary of Fair Value and Amortized Cost of Cash Equivalents and Available-for-sale Investments by Major Security Type (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents and investments, Amortized cost	$ 211,650	$ 229,432
Cash equivalents and investments, Unrealized gain	7	82
Cash equivalents and investments, Unrealized loss		(1)
Cash equivalents and investments, Estimated Fair Value	211,657	229,513
Cash equivalents, Estimated Fair Value	89,221	139,779
Short-term investments	122,436	89,734
Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents, Amortized Cost	89,221	127,783
Cash equivalents, Estimated Fair Value	89,221	127,783
U.S. treasury bills
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	6,000	29,995
Investments, Unrealized Gain	0	2
Investments, Unrealized Loss	0	0
Investments, Estimated Fair Value	6,000	29,997
Corporate Debt Securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	6,500	23,126
Investments, Unrealized Gain	6	75
Investments, Unrealized Loss	0	0
Investments, Estimated Fair Value	6,506	23,201
U.S. Government Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	5,037	5,067
Investments, Unrealized Gain	1	0
Investments, Unrealized Loss	0	(1)
Investments, Estimated Fair Value	5,038	5,066
Commercial Paper
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost	104,892	41,460
Investments, Unrealized Gain	0	0
Investments, Unrealized Loss	0	0
Investments, Estimated Fair Value	$ 104,892	41,460
Asset Backed Securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments, Amortized Cost		2,001
Investments, Unrealized Gain		5
Investments, Unrealized Loss		0
Investments, Estimated Fair Value		$ 2,006

Cash equivalents and available for sale debt securities accumulated gross unrealized gain before tax.

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Cash equivalents and available for sale debt securities accumulated gross unrealized loss before tax.

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Cash equivalents and available for sale debt securities amortized cost basis.

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Cash equivalents and available for sale securities debt securities.

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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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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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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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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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