Cash Equivalents and Marketable Securities - Schedule of Estimated Fair Value of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	$ 21,856	$ 77,600
Cash equivalents, gross unrealized losses	(1)	(3)
Cash equivalents, estimated fair value	21,855	77,597
Marketable securities, amortized cost	93,826	56,183
Marketable securities, gross unrealized gains	5	2
Marketable securities, gross unrealized losses	(18)	(7)
Marketable securities, estimated fair value	93,813	56,178
Money market funds
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	8,951	6,700
Cash equivalents, estimated fair value	8,951	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	24,295	53,183
Marketable securities, gross unrealized gains	1	1
Marketable securities, gross unrealized losses		(7)
Marketable securities, estimated fair value	24,296	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	10,399
Cash equivalents, gross unrealized losses	(1)
Cash equivalents, estimated fair value	10,398
Marketable securities, amortized cost	47,156
Marketable securities, gross unrealized gains	4
Marketable securities, gross unrealized losses	(7)
Marketable securities, estimated fair value	47,153
Corporate bonds
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, amortized cost	2,506
Cash equivalents, estimated fair value	2,506
Marketable securities, amortized cost	22,375	3,000
Marketable securities, gross unrealized gains		1
Marketable securities, gross unrealized losses	(11)
Marketable securities, estimated fair value	$ 22,364	$ 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).

+ References

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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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