Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	$ 67,691	$ 60,755
Recurring
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	69,575	70,011
Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	1,884	1,258
Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	67,691	68,753
Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	0	0
Recurring \| Commercial paper
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	15,203	18,229
Recurring \| Commercial paper \| Cash and Cash Equivalents
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value		8,000
Recurring \| Commercial paper \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring \| Commercial paper \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	15,203	18,229
Recurring \| Commercial paper \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring \| Corporate notes
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	52,488	50,524
Recurring \| Corporate notes \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring \| Corporate notes \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	52,488	50,524
Recurring \| Corporate notes \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Recurring \| Money market funds
Liabilities that are measured at fair value on a recurring basis
Money market funds	1,884	1,258
Recurring \| Money market funds \| Level 1
Liabilities that are measured at fair value on a recurring basis
Money market funds	1,884	1,258
Recurring \| Money market funds \| Level 2
Liabilities that are measured at fair value on a recurring basis
Money market funds	0	0
Recurring \| Money market funds \| Level 3
Liabilities that are measured at fair value on a recurring basis
Money market funds	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Publisher FASB
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-Section 50
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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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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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