Net Carrying Values of Debt Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	May 31, 2022	May 31, 2021
Available-for-Sale Debt Securities, Amortized Cost
Less than one year, amortized cost	$ 6,057
One year through five years, amortized cost	14,866
Six years through ten years, amortized cost	3,219
After ten years, amortized cost	2,527
Available-for-Sale Debt Securities, Amortized Cost	26,669	$ 26,297
Available-for-Sale Debt Securities, Fair Value
Less than one year, fair value	6,048
One year through five years, fair value	14,201
Six years through ten years, fair value	2,993
After ten years, fair value	2,152
Available-for-sale debt securities, fair value	$ 25,394	$ 26,745

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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