Income Taxes - Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Deferred tax assets: | ||
| Accrued expenses not currently deductible | $ 294.9 | $ 256.7 |
| Stock-based compensation expense | 59.8 | 56.0 |
| Foreign tax credits | 9.6 | 8.8 |
| Fixed and intangible assets | 80.7 | 216.8 |
| Net operating losses | 57.4 | 59.3 |
| Disallowed business interest expense carryforward | 0.0 | 30.9 |
| Unrealized investment losses, net | 106.1 | 98.4 |
| Other | 32.2 | 28.5 |
| Deferred tax assets, gross | 640.7 | 755.4 |
| Less: valuation allowances | (24.1) | (23.8) |
| Deferred tax assets, net | 616.6 | 731.6 |
| Deferred tax liabilities: | ||
| Deferred contract costs | 664.9 | 654.0 |
| Prepaid expenses | 122.3 | 103.1 |
| Prepaid retirement benefits | 76.6 | 53.1 |
| Tax on unrepatriated earnings | 10.4 | 12.0 |
| Other | 17.3 | 16.9 |
| Deferred tax liabilities | 891.5 | 839.1 |
| Net deferred tax (liabilities)/assets | $ (274.9) | $ (107.5) |
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- Definition Deferred Tax Assets, Disallowed Business Interest Expense Carryforward No definition available.
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- Definition Deferred Tax Assets, Fixed And Intangible Assets No definition available.
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- Definition Deferred Tax Liabilities, Tax Deferred Expense, Compensation And Benefits, Postretirement Benefits No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from unrealized loss on investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from capitalized costs classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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