Net Carrying Values of Debt Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	May 31, 2023	May 31, 2022
Available-for-Sale Debt Securities, Amortized Cost
Less than one year, amortized cost	$ 5,308
One year through five years, amortized cost	19,172
Six years through ten years, amortized cost	2,023
After ten years, amortized cost	2,485
Available-for-Sale Debt Securities, Amortized Cost	28,988	$ 26,669
Available-for-Sale Debt Securities, Fair Value
Less than one year, fair value	5,143
One year through five years, fair value	18,334
Six years through ten years, fair value	1,742
After ten years, fair value	1,943
Available-for-sale debt securities, fair value	$ 27,162	$ 25,394

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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