Contractual Maturities of Investments in Debt Securities Held (Detail) $ in Thousands	Mar. 31, 2024 USD ($)
Schedule of Available-for-sale Securities
Due within one year, cost	$ 41,308
Due after 1 year through 5 years, cost	26,360
Due after 5 years through 10 years, cost	7,760
Due after 10 years, cost	37,094
Total, cost	112,522
Due within one year, fair market value	41,300
Due after 1 year through 5 years, fair market value	25,819
Due after 5 years through 10 years, fair market value	7,405
Due after 10 years, fair maket value	29,445
Total, fair market value	$ 103,969