Tax - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
|---|---|---|
| Deferred tax assets: | ||
| Property, plant and equipment | $ 0.0 | $ 1.1 |
| Share-based compensation | 42.1 | 42.6 |
| Intangibles | 0.0 | 0.0 |
| Provisions | 11.2 | 8.4 |
| Net operating loss and tax credit carryforwards | 7.5 | 5.5 |
| Other | 3.2 | 1.4 |
| Total deferred tax assets | 64.0 | 59.0 |
| Valuation allowance | (6.6) | (5.0) |
| Net deferred tax assets | 57.4 | 54.0 |
| Deferred tax liabilities: | ||
| Intangibles | (0.1) | (0.2) |
| Property, plant and equipment | (2.6) | 0.0 |
| Other | (5.5) | (5.2) |
| Net deferred tax assets | $ 49.2 | $ 48.6 |
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill. 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 and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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- References No definition available.
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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 temporary differences from property, plant, and equipment. 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 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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- References No definition available.
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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 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 from property, plant, and equipment. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Deferred tax assets net operating loss and tax credit carryforwards. No definition available.
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- Definition Deferred tax assets provisions. No definition available.
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