Investment (Income), Net - Net (Gain) on Marketable Securities (Detail) - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2025	Aug. 31, 2024
Net Loss (Gain) on Marketable Securities
Unrealized (gains) on marketable equity securities	$ (8,586)	$ (5,778)
Realized (gains) on marketable equity securities	(97)	(195)
Realized losses on available-for-sale debt securities	10	2
Net (gain) on marketable securities	$ (8,673)	$ (5,971)

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-14

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