Income Taxes (Components of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	May 31, 2026	May 31, 2025
Income Tax Disclosure [Abstract]
Compensation and employee benefit liabilities	$ 71.5	$ 69.2
Other current liabilities	27.2	15.8
Tax credit carry forward	0.8	10.4
Stock-based compensation	16.2	24.4
Unrealized losses on AFS securities	13.1	13.6
Capitalization of research and development	26.9	133.4
Leases	16.0	15.6
Net operating loss ("NOL") carry forwards	15.9	28.9
Tax benefit of uncertain tax positions	20.4	18.3
Gross deferred tax assets	208.0	329.6
Deferred contract costs	173.3	149.7
Capitalized software	177.0	167.7
Goodwill, intangible assets, and fixed assets	374.4	431.8
Operating lease right-of-use assets	14.0	12.7
Other	6.7	6.6
Gross deferred tax liabilities	745.4	768.5
Net deferred tax liability	$ (537.4)	$ (438.9)

Deferred Tax Assets, Lease Liability

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

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Deferred Tax Liabilities Deferred Expense Contract Costs

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Deferred tax liabilities, goodwill, intangible assets and fixed assets.

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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 operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from unrealized losses in other comprehensive income.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit 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 before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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

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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 capitalized software.

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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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