Income Taxes - Summary of Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Deferred tax assets: | ||
| Pensions | $ 12.8 | $ 26.3 |
| Postretirement provisions | 5.6 | 11.3 |
| Non-equity compensation | 8.8 | 9.6 |
| Net operating loss carryforwards | 8.4 | 8.3 |
| Tax credit carryforwards | 0.8 | 1.6 |
| Operating lease liabilities | 6.7 | 8.1 |
| Other | 20.5 | 21.0 |
| Gross deferred tax assets | 63.6 | 86.2 |
| Valuation allowances | (4.9) | (2.6) |
| Total deferred tax assets | 58.7 | 83.6 |
| Deferred tax liabilities: | ||
| Depreciation | 215.0 | 198.4 |
| Intangible assets | 0.2 | 2.4 |
| Inventories | 26.8 | 28.3 |
| Operating lease right-of-use assets | 5.1 | 6.4 |
| Other | 3.0 | 3.1 |
| Total deferred tax liabilities | 250.1 | 238.6 |
| Deferred tax liabilities, net | $ 191.4 | $ 155.0 |
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- Definition Deferred Tax Assets, Non Equity Compensation No definition available.
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- Definition Deferred Tax Assets, Operating Lease, Liability No definition available.
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- Definition Represents the amount of deferred tax liabilities attributable to taxable temporary differences from depreciation. No definition available.
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- References No definition available.
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- References 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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- 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 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. 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 pension benefits. 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 postretirement benefits. 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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- Definition Amount of deferred tax consequences attributable to taxable temporary differences derived from inventory. 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 intangible assets other than goodwill. 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 leasing arrangements. 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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