Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Average Stock Price Prior To End Of Vesting Period, Period

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Number Of Shares Vesting If Price Targets Met, Potential Percentage

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Non-Option Equity Instruments, Maximum Exercisable

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Intended To Be Settled In Cash, Number

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Intended To Be Settled In Cash, Value

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Exchanged

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Issued From Exchange

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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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, with jurisdictional netting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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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.

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Share-Based Compensation - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
	May 12, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Jan. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 3.9	$ 3.7
Related tax benefits (expense)		1.0	1.4
Non-current deferred tax assets		58.3		$ 70.5
Income tax expense benefit (expense)		0.7	(0.9)
Stock options exchanged (in shares)	4,279,463
Stock options issued from exchange (in shares)	1,728,795
Shares paid for tax withholding for share-based compensation, cost		1.9
Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-current deferred tax assets					$ 0.6
Income tax expense benefit (expense)		$ 0.7	$ (0.9)
Accumulated Deficit \| Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative effect adjustment					(0.9)
Additional Paid-In Capital \| Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative effect adjustment					$ 1.5
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares paid for tax withholding for share-based compensation (in shares)		360,680	640,974
Shares paid for tax withholding for share-based compensation, cost		$ 1.8	$ 1.5
Nonvested (in shares)		1,315,148		2,352,490
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares paid for tax withholding for share-based compensation (in shares)		1,722	0
Shares paid for tax withholding for share-based compensation, cost		$ 0.1	$ 0.0
Nonvested (in shares)		1,157,415		1,183,500
Performance-Based Restricted Stock Units (PBRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average stock price prior to end of vesting period, period		60 days
Maximum exercisable (in shares)		9,378,874
Nonvested (in shares)		4,263,027		4,785,900
Nonvested intended to be settled in cash (in shares)		983,472
Nonvested intended to be settled in cash, value		$ 1.2
Minimum \| Performance-Based Restricted Stock Units (PBRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vesting if price targets met, potential percentage		0.00%
Maximum \| Performance-Based Restricted Stock Units (PBRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vesting if price targets met, potential percentage		350.00%