Marketable Securities - Summary of Available-for-Sale Debt Securities by Asset Type (Detail) - USD ($) $ in Thousands	May 31, 2025	May 31, 2024
Debt Securities, Available-for-sale [Line Items]
Available-for-Sale Debt Securities, Amortized Cost	$ 25,350	$ 28,484
Available-for-Sale Debt Securities, Gross Unrealized Gains	73	9
Available-for-Sale Debt Securities, Gross Unrealized Losses	(1,100)	(1,796)
Available-for-Sale Debt Securities, Fair Value (Net Carrying Amount)	24,323	26,697
U.S. Treasury and other government
Debt Securities, Available-for-sale [Line Items]
Available-for-Sale Debt Securities, Amortized Cost	25,218	28,338
Available-for-Sale Debt Securities, Gross Unrealized Gains	69	5
Available-for-Sale Debt Securities, Gross Unrealized Losses	(1,087)	(1,784)
Available-for-Sale Debt Securities, Fair Value (Net Carrying Amount)	24,200	26,559
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-Sale Debt Securities, Amortized Cost	132	146
Available-for-Sale Debt Securities, Gross Unrealized Gains	4	4
Available-for-Sale Debt Securities, Gross Unrealized Losses	(13)	(12)
Available-for-Sale Debt Securities, Fair Value (Net Carrying Amount)	$ 123	$ 138

Amount 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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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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