Contractual Maturities of Investments in Debt Securities Held (Detail) $ in Thousands	Dec. 31, 2021 USD ($)
Schedule of Available-for-sale Securities
Due within one year, cost	$ 244,213
Due after 1 year through 5 years, cost	41,459
Due after 5 years through 10 years, cost	6,085
Due after 10 years, cost	34,392
Total, cost	326,149
Due within one year, fair market value	244,231
Due after 1 year through 5 years, fair market value	41,377
Due after 5 years through 10 years, fair market value	6,434
Due after 10 years, fair maket value	38,823
Total, fair market value	$ 330,865

Amortized cost 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 sixth through tenth 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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