Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Percent Expected To Vest

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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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- Definition

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

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-Publisher FASB
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

The number of grants made 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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- 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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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.

+ References

No definition available.

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- Definition

Weighted average price of options that were either forfeited or expired.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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Share-Based Compensation Restricted Stock Activity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Percent Expected To Vest			75.10%	74.80%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Expense			$ 17.5	$ 15.1	$ 12.7
Compensation Cost Not yet Recognized	$ 39.0		39.0
Vested in Period, Total Fair Value			$ 15.3	$ 11.7	$ 9.3
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Weighted Average Grant Date Fair Value, Unvested	$ 85.43	$ 72.65	$ 85.43	$ 64.25		$ 56.38
Unvested restricted shares		871,117		859,853		841,634
Granted shares			190,020	233,400	219,400
Weighted Average Grant Date Fair Value		$ 87.12	$ 117.47		$ 79.38
Vested in Period			(237,406)	(214,111)	(196,412)
Weighted Average Grant Date Fair Value, Vested		54.69	$ 64.46		$ 47.60
Forfeited in Period	(813,041)		(10,690)	(8,025)	(4,769)
Weighted Average Exercise Price, Forfeitures		$ 72.16	$ 79.58		$ 56.43
Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted shares				16,500
Weighted Average Grant Date Fair Value				$ 88.30
Executive Officer [Member] \| Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Award Vesting Rights, Percentage			100.00%	100.00%
Share-based Payment Arrangement, Tranche One [Member] \| Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Award Vesting Rights, Percentage				35.00%
Share-based Payment Arrangement, Tranche Two [Member] \| Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted shares				50,100
Weighted Average Grant Date Fair Value				$ 86.97
Award Vesting Rights, Percentage				35.00%
Share-based Payment Arrangement, Tranche Three [Member] \| Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Award Vesting Rights, Percentage				20.00%
Share-based Compensation Award, Tranche Four [Member] \| Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Award Vesting Rights, Percentage				5.00%
Share-based Compensation Award, Tranche Five [Member] \| Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Award Vesting Rights, Percentage				5.00%
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Price	$ 115.39		$ 115.39	$ 87.24
Market Condition [Member] \| Executive Officer [Member] \| Two Thousand Fifteen Equity Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted shares			66,000	90,000
Weighted Average Grant Date Fair Value			$ 115.39	$ 65.24