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

No definition available.

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- Definition

Payout Percentage for Exceeding Performance Target

+ References

No definition available.

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- Definition

Performance Period

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ 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)(iii)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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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).

+ 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)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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).

+ 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)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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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)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ 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)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested 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)(2)(iii)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ 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 (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ 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)(iii)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

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

+ References

No definition available.

+ Details

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Long-term Equity-based Compensation - Activity Related to Nonvested Restricted Stock (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			0 Months Ended	36 Months Ended	0 Months Ended	36 Months Ended	0 Months Ended	36 Months Ended	0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 01, 2014	Dec. 31, 2013	Feb. 02, 2013	Dec. 31, 2012	Feb. 03, 2012	Dec. 31, 2011	Jan. 31, 2015
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in Period, Total Fair Value	$ 3.6	$ 4.1	$ 4.0
Income tax benefit from share-based compensation	$ 1.2	$ 1.4	$ 1.4
Time Vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Balance at Beginning of Year, Restricted Shares	101,627
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)	$ 31.48
Grants in Period	2,000
Grants in Period, Weighted Average Grant Date Fair Value (per share)	$ 38.59
Vested in Period	(25,568)
Vested in Period, Weighted Average Grant Date Fair Value (per share)	$ 30.56
Forfeited in Period	(24,964)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)	$ 30.96
Nonvested Balance at End of Year, Restricted Shares	53,095
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)	$ 32.42
Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	3 years
Nonvested Balance at Beginning of Year, Restricted Shares	176,800
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)	$ 39.54
Grants in Period	0
Grants in Period, Weighted Average Grant Date Fair Value (per share)	$ 0.00
Vested in Period	(54,934)
Vested in Period, Weighted Average Grant Date Fair Value (per share)	$ 39.83
Forfeited in Period	(11,241)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)	$ 40.75
Nonvested Balance at End of Year, Restricted Shares	110,625
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)	$ 39.28
Reduction in share authorization if maximum performance level is met or exceeded (shares)	517,500
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	0
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)	$ 0.00
Grants in Period	41,925
Grants in Period, Weighted Average Grant Date Fair Value (per share)	$ 36.56
Vested in Period	(9,351)
Vested in Period, Weighted Average Grant Date Fair Value (per share)	$ 36.47
Forfeited in Period	(2,550)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)	$ 36.47
Nonvested Balance at End of Year, Restricted Shares	30,024
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)	$ 36.60
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	0
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)	$ 0.00
Grants in Period	66,575
Grants in Period, Weighted Average Grant Date Fair Value (per share)	$ 40.50
Vested in Period	0
Vested in Period, Weighted Average Grant Date Fair Value (per share)	$ 0.00
Forfeited in Period	(4,700)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)	$ 40.50
Nonvested Balance at End of Year, Restricted Shares	61,875
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)	$ 40.50
Performance Period, 2014 to 2016 [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	61,875
Reduction in share authorization if maximum performance level is met or exceeded (shares)	185,625
Performance Period, 2013 to 2015 [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		52,850			52,850
Reduction in share authorization if maximum performance level is met or exceeded (shares)		158,550			158,550
Performance Period, 2011 to 2013 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage for exceeding performance target					118.00%
Shares issued during the period				9,014
Performance Period, 2010 to 2012 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage for exceeding performance target							114.00%
Shares issued during the period						6,996
Performance Period, 2009 to 2011 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage for exceeding performance target									183.00%
Shares issued during the period								40,727
Subsequent Event [Member] \| Performance Period, 2012 to 2014 [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										57,775