Available-for-Sale Debt Securities by Original Contractual Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Investments Debt And Equity Securities [Abstract]
One year or less, amortized cost	$ 32,200	$ 44,873
Greater than one year and less than five years, amortized cost	51,042	43,046
Amortized Cost	83,242	87,919
One year or less, fair value	32,044	44,952
Greater than one year and less than five years, fair value	49,045	42,818
Total available-for-sale securities fair value	$ 81,089	$ 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).

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