Share-Based Compensation Expenses (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Share-Based Payment Arrangement [Abstract] | ||||
| Option awards | $ 1.5 | $ 2.2 | $ 9.7 | $ 9.3 |
| Other share-based awards | 6.3 | 12.4 | 26.7 | 29.4 |
| Total share-based compensation before tax | 7.8 | 14.6 | 36.4 | 38.7 |
| Tax benefit | 1.9 | 3.5 | 8.9 | 9.4 |
| Total share-based compensation expense included in net income (loss) | $ 5.9 | $ 11.1 | $ 27.5 | $ 29.3 |
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- Definition Restricted Stock Or Unit Expense, Net Of Performance Value Adjustment No definition available.
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after tax, of expense for award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of noncash expense for option under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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