Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2020 |
Sep. 30, 2019 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Share-based compensation expense | $ 15.4 | $ 9.2 | $ 37.9 | $ 29.7 |
| Unrecognized compensation cost on non-vested stock awards | 87.2 | $ 87.2 | ||
| Unrecognized compensation cost on non-vested stock awards, weighted-average period of recognition | 1 year 8 months 12 days | |||
| Total vesting date fair value of stock units | $ 1.3 | $ 0.2 | $ 12.3 | $ 11.1 |
| SARs [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| SARs granted | 0 | 0 | 0 | 0 |
| Total intrinsic value of awards exercised for SARs | $ 38.5 | $ 2.4 | $ 50.2 | $ 19.6 |
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- Definition Intrinsic value of awards exercised for stock appreciation rights. No definition available.
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Net number of non-option equity instruments granted to participants. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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