Consolidated Statement of Changes in Stockholders Equity (Parenthetical) - USD ($) $ in Millions	12 Months Ended
May 31, 2026	May 31, 2025	May 31, 2024
Statement of Stockholders' Equity [Abstract]
Pension and postretirement adjustments, tax portion	$ 0.3	$ 0.2	$ 0.2

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Period Type:	duration