Cash Equivalents and Marketable Securities - Schedule of Estimated Fair Value of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	$ 77,600	$ 15,520
Cash equivalents, gross unrealized losses	(3)
Cash equivalents, estimated fair value	77,597	15,520
Marketable securities, amortized cost	56,183	52,645
Marketable securities, gross unrealized gains	2	60
Marketable securities, gross unrealized losses	(7)	(9)
Marketable securities, estimated fair value	56,178	52,696
Corporate bonds
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, amortized cost	3,000	39,714
Marketable securities, gross unrealized gains	1	45
Marketable securities, gross unrealized losses		(9)
Marketable securities, estimated fair value	3,001	39,750
Commercial paper
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost		2,247
Cash equivalents, estimated fair value		2,247
Marketable securities, amortized cost		12,931
Marketable securities, gross unrealized gains		15
Marketable securities, estimated fair value		12,946
Money market funds
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	6,700	7,023
Cash equivalents, estimated fair value	6,700	7,023
U.S. treasury securities
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	4,005
Cash equivalents, gross unrealized losses	(1)
Cash equivalents, estimated fair value	4,004
Marketable securities, amortized cost	53,183
Marketable securities, gross unrealized gains	1
Marketable securities, gross unrealized losses	(7)
Marketable securities, estimated fair value	53,177
U.S. government agency securities
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	66,895
Cash equivalents, gross unrealized losses	(2)
Cash equivalents, estimated fair value	$ 66,893
Reverse repurchase agreements
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost		6,250
Cash equivalents, estimated fair value		$ 6,250

Cash equivalents unrealized losses.

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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), 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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