Contractual Maturities of Investments in Debt Securities Held (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Schedule of Available-for-sale Securities
Due within one year, cost	$ 137,144
Due after 1 year through 5 years, cost	15,264
Due after 5 years through 10 years, cost	14,436
Due after 10 years, cost	37,999
Total, cost	204,843
Due within one year, fair market value	137,303
Due after 1 year through 5 years, fair market value	15,351
Due after 5 years through 10 years, fair market value	14,576
Due after 10 years, fair maket value	41,903
Total, fair market value	$ 209,133

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 fiscal year through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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