Cash Equivalents and Marketable Securities - Schedule of Estimated Fair Value of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	$ 16,131	$ 77,600
Cash equivalents, gross unrealized losses		(3)
Cash equivalents, estimated fair value	16,131	77,597
Marketable securities, amortized cost	87,776	56,183
Marketable securities, gross unrealized gains	4	2
Marketable securities, gross unrealized losses	(17)	(7)
Marketable securities, estimated fair value	87,763	56,178
Money market funds
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	12,131	6,700
Cash equivalents, estimated fair value	12,131	6,700
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
Commercial paper
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	4,000
Cash equivalents, estimated fair value	4,000
Marketable securities, amortized cost	70,696
Marketable securities, gross unrealized gains	4
Marketable securities, gross unrealized losses	(11)
Marketable securities, estimated fair value	70,689
Corporate bonds
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, amortized cost	17,080	3,000
Marketable securities, gross unrealized gains		1
Marketable securities, gross unrealized losses	(6)
Marketable securities, estimated fair value	$ 17,074	$ 3,001

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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-Publisher FASB
-Name Accounting Standards Codification
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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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