Compensation Related Costs Share Based Payments Disclosure [Line Items]

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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- Definition

Amount of commitment made to pay deferred cash remuneration.

+ References

No definition available.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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- Definition

Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
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-Topic 710
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Deferred Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Payments Disclosure [Line Items]
Description of vesting term for awards granted	Awards granted under the plan are generally amortized ratably over a three to five-year service period following the date of the grant.
Deferred compensation payable	$ 14.5	$ 12.1
Unrecognized deferred cash compensation (prior to the consideration of forfeitures)	$ 6.0
Deferred compensation arrangement with individual, maximum contractual term	8 months 12 days
Compensation expense from deferred compensation	$ 8.9	7.7	$ 13.1
Minimum
Share Based Payments Disclosure [Line Items]
Service period for deferred compensation payable	3 years
Maximum
Share Based Payments Disclosure [Line Items]
Service period for deferred compensation payable	5 years
Restricted stock units
Share Based Payments Disclosure [Line Items]
Compensation expense from the vesting of restricted stock units	$ 45.8	$ 38.4	$ 40.2
Weighted average grant date fair value for restricted stock units granted (usd per share)	$ 22.55	$ 18.94	$ 20.87
Unrecognized restricted stock units compensation expense	$ 58.4
Unrecognized restricted stock units compensation expense, weighted average recognition period	1 year 8 months 12 days
Restricted stock units \| Minimum
Share Based Payments Disclosure [Line Items]
Stock units granted, ratable vesting period	3 years
Restricted stock units \| Maximum
Share Based Payments Disclosure [Line Items]
Stock units granted, ratable vesting period	5 years