Annual Awards of Deferred Stock Units to be Issued to each Non-Employee Director

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Number of Additional Shares To Be Granted If Maximum Perfornance Level Is Met or Exceeded

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Reduction in Share Authorization if Maximum Performance Level is Met or Exceeded

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Share Based Compensation Arrangement By Share Based Payment Award, Automatic Annual Grant, Non-Employee Directors, Options

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Share Based Compensation Arrangement By Share Based Payment Award, Automatic Annual Grant, Non-Employee Directors, Options, Expiration Date

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Tax Benefits

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Deferred Stock Unit, Vested in Period, Fair Value

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- Definition

Share-based Compensation,Initial Grant For Non-Employee Director, Options

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- Definition

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

+ 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)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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

Number of shares (or other type of equity) forfeited during the period.

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No definition available.

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Long-term Equity-based Compensation - Activity Related to Nonvested Restricted Stock (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Feb. 04, 2017	Feb. 04, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of DSUs that vested during the years			$ 0.9	$ 0.5	$ 0.1
Annual Awards of Deferred Stock Units to be Issued to each Non-Employee Director					500
Initial grant for non-employee director, shares					4,000
Automatic annual grant, non-employee directors, options					4,000
Automatic annual grant, non-employee directors, options, expiration date					10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in Period, Total Fair Value			3.2	1.3	$ 1.4
Income tax benefit from share-based compensation			$ 1.1	$ 0.5	$ 0.5
Time Vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Balance at Beginning of Year, Restricted Shares			16,000
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)			$ 34.69
Grants in Period			0
Grants in Period, Weighted Average Grant Date Fair Value (per share)			$ 0.00
Vested in Period			(14,000)
Vested in Period, Weighted Average Grant Date Fair Value (per share)			$ 34.13
Forfeited in Period			(2,000)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)			$ 38.59
Nonvested Balance at End of Year, Restricted Shares			0	16,000
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)			$ 0.00	$ 34.69
Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in share authorization if maximum performance level is met or exceeded (shares)			677,949
Time Vested Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Balance at Beginning of Year, Restricted Shares			158,361
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)			$ 33.56
Grants in Period			84,331
Grants in Period, Weighted Average Grant Date Fair Value (per share)			$ 44.70
Vested in Period			(57,016)
Vested in Period, Weighted Average Grant Date Fair Value (per share)			$ 33.65
Forfeited in Period			(55,429)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)			$ 34.46
Nonvested Balance at End of Year, Restricted Shares			130,247	158,361
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)			$ 40.34	$ 33.56
Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Balance at Beginning of Year, Restricted Shares			227,584
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)			$ 34.55
Grants in Period			100,620
Grants in Period, Weighted Average Grant Date Fair Value (per share)			$ 44.32
Forfeited in Period			(102,221)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)			$ 38.96
Nonvested Balance at End of Year, Restricted Shares			225,983	227,584
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)			$ 36.90	$ 34.55
Performance Period, 2017 to 2019 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Additional Shares To Be Granted If Maximum Performance Level Is Met or Exceeded			84,383
Reduction in share authorization if maximum performance level is met or exceeded (shares)			253,149
Performance Period, 2016 to 2018 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Additional Shares To Be Granted If Maximum Performance Level Is Met or Exceeded			107,638
Reduction in share authorization if maximum performance level is met or exceeded (shares)			322,914
Performance Period, 2015 to 2017 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Additional Shares To Be Granted If Maximum Performance Level Is Met or Exceeded			33,962
Reduction in share authorization if maximum performance level is met or exceeded (shares)			101,886
Performance Period, 2014 to 2016 [Member] \| Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited in Period	(43,207)
Performance Period, 2013 to 2015 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Share-based Compensation, Forfeited		51,400