Fair Value Measurements - Estimated Value of Cash Equivalents and Debt Securities and Gross Unrealized Holding Gains and Losses (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Cash Equivalents and Investment Securities [Line Items]
Cash equivalents, Amortized cost	$ 40,483	$ 13,520
Cash equivalents, Estimated Fair Value	40,483
Debt securities, Amortized cost	86,677	84,005
Debt securities, Unrealized loss	(522)	(149)
Debt securities, Estimated Fair Value	86,155	83,856
Assets, Fair Value	126,638	97,376
Short-Term Debt [Member]
Cash Equivalents and Investment Securities [Line Items]
Debt securities, Estimated Fair Value	86,155	66,594
Long-term Debt
Cash Equivalents and Investment Securities [Line Items]
Debt securities, Estimated Fair Value		17,262
Corporate Debt Securities [Member]
Cash Equivalents and Investment Securities [Line Items]
Debt securities, Amortized cost	33,461	41,576
Debt securities, Unrealized loss	(197)	(65)
Debt securities, Estimated Fair Value	33,264	41,511
Assets, Fair Value	33,264	41,511
US Government Bonds [Member]
Cash Equivalents and Investment Securities [Line Items]
Debt securities, Amortized cost	42,312	42,429
Debt securities, Unrealized loss	(325)	(84)
Debt securities, Estimated Fair Value	41,987	42,345
Assets, Fair Value	41,987	42,345
Money Market Funds [Member]
Cash Equivalents and Investment Securities [Line Items]
Cash equivalents, Amortized cost	40,483	13,520
Cash equivalents, Estimated Fair Value	40,483
Assets, Fair Value	40,483	13,520
Commercial Paper [Member]
Cash Equivalents and Investment Securities [Line Items]
Debt securities, Amortized cost	10,904
Debt securities, Estimated Fair Value	10,904
Assets, Fair Value	10,904
Cash Equivalents [Member]
Cash Equivalents and Investment Securities [Line Items]
Cash equivalents, Estimated Fair Value	$ 40,483	$ 13,520

Cash equivalents amortized cost.

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- Definition

Cash equivalents and investment securities.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
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- Definition

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).

+ References

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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).

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- Definition

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.

+ References

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