Net Carrying Values of Debt Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	May 31, 2024	May 31, 2023
Available-for-Sale Debt Securities, Amortized Cost
Less than one year, amortized cost	$ 6,589
One year through five years, amortized cost	16,548
Six years through ten years, amortized cost	2,929
After ten years, amortized cost	2,418
Available-for-Sale Debt Securities, Amortized Cost	28,484	$ 28,988
Available-for-Sale Debt Securities, Fair Value
Less than one year, fair value	6,502
One year through five years, fair value	15,816
Six years through ten years, fair value	2,638
After ten years, fair value	1,741
Available-for-sale debt securities, fair value	$ 26,697	$ 27,162

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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