The Business and Summary of Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	$ 14,705	$ 72,970
Fair value, measurements, recurring
Fair Value, Separate Account Investment
Cash equivalents	20,030	11,841
Short-term investments, available-for-sale	14,705	72,970
Long-term investments		2,022
Total assets	34,735	86,833
Fair value, measurements, recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Cash equivalents	20,030	11,841
Short-term investments, available-for-sale	4,488	2,523
Long-term investments		2,022
Total assets	24,518	16,386
Fair value, measurements, recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Cash equivalents	0	0
Short-term investments, available-for-sale	10,217	70,447
Long-term investments		0
Total assets	10,217	70,447
Fair value, measurements, recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Cash equivalents	0	0
Short-term investments, available-for-sale	0	0
Long-term investments		0
Total assets	0	0
U.S. treasury securities \| Fair value, measurements, recurring
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	9,474	7,517
Long-term investments		2,022
U.S. treasury securities \| Fair value, measurements, recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	4,488	2,523
Long-term investments		2,022
U.S. treasury securities \| Fair value, measurements, recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	4,986	4,994
Long-term investments		0
U.S. treasury securities \| Fair value, measurements, recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	0	0
Long-term investments		0
Commercial paper \| Fair value, measurements, recurring
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	2,476	34,887
Commercial paper \| Fair value, measurements, recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	0	0
Commercial paper \| Fair value, measurements, recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	2,476	34,887
Commercial paper \| Fair value, measurements, recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	0	0
Corporate bonds \| Fair value, measurements, recurring
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	2,755	30,566
Corporate bonds \| Fair value, measurements, recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	0	0
Corporate bonds \| Fair value, measurements, recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	2,755	30,566
Corporate bonds \| Fair value, measurements, recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Short-term investments, available-for-sale	0	0
Money market funds \| Fair value, measurements, recurring
Fair Value, Separate Account Investment
Cash equivalents	20,030	11,841
Money market funds \| Fair value, measurements, recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Separate Account Investment
Cash equivalents	20,030	11,841
Money market funds \| Fair value, measurements, recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Separate Account Investment
Cash equivalents	0	0
Money market funds \| Fair value, measurements, recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Separate Account Investment
Cash equivalents	$ 0	$ 0

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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 noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26626-111562

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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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