Available-for-Sale Debt Securities by Original Contractual Maturity (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
One year or less, amortized cost	$ 26,337	$ 44,873
Greater than one year and less than five years, amortized cost	57,038	43,046
Amortized Cost	83,375	87,919
One year or less, fair value	26,176	44,952
Greater than one year and less than five years, fair value	54,011	42,818
Total available-for-sale securities fair value	$ 80,187	$ 87,770

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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