Income Taxes - Significant Components of Deferred Income Tax Assets and Liabilities (Detail) - USD ($)	May 31, 2025	May 31, 2024
Deferred income tax assets related to:
Inventories	$ 17,348,000	$ 17,772,000
Accrued compensation and benefits	15,430,000	17,649,000
Other accrued and prepaid expenses, net	21,294,000	19,058,000
Deferred income and other long-term liabilities	24,880,000	31,204,000
Credit, net operating, interest and capital loss carryforwards	60,457,000	87,590,000
Research and development	42,258,000	33,076,000
Pension and other postretirement benefits	5,069,000
Total Deferred Income Tax Assets	186,736,000	206,349,000
Less: valuation allowances	(49,167,000)	(30,021,000)
Net Deferred Income Tax Assets	137,569,000	176,328,000
Deferred income tax (liabilities) related to:
Depreciation	(136,966,000)	(132,007,000)
Amortization of intangibles	(77,142,000)	(125,553,000)
Unremitted foreign earnings	0	(4,055,000)
Net unrealized gain on securities	(372,000)	(1,305,000)
Pension and other postretirement benefits		(1,108,000)
Total Deferred Income Tax (Liabilities)	(214,480,000)	(264,028,000)
Deferred Income Tax Assets (Liabilities), Net	$ (76,911,000)	$ (87,700,000)

Deferred tax assets credit net operating interest and capital loss carryforwards.

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Deferred tax assets deferred income and other long-term liabilities.

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Deferred tax assets, tax deferred expense, compensation and benefits, pensions and other postretirement benefits.

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Deferred tax assets, tax deferred expense, reserves and accruals, other accrued and prepaid expenses, net.

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Deferred tax liabilities pension and other postretirement benefits.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from in-process research and development cost acquired in business combination or from joint venture formation or both.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets including goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on trading securities.

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