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Represents the performance period of other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

No definition available.

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- Definition

Represents the period, from the date of grant, that award can be exercised once they have vested.

+ References

No definition available.

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- Definition

Represents the percentage of target awards earned for the performance period.

+ References

No definition available.

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- Definition

The percentage of target shares, an employee can earn, under the plan.

+ References

No definition available.

+ Details

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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 50

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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 (i)

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

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(1)

-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

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- Definition

Number of non-option equity instruments exercised by participants.

+ 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)(2)

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

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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 (a)(3)

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

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Stock-Based Compensation (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other information
Allocated Share-based Compensation Expense	$ 4.7	$ 3.5	$ 2.9
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period from date of grant	10 years
Other information
Total unrecognized stock-based compensation expense, net of estimated forfeitures	0.6
Weighted average vesting period	10 months 24 days
Maximum [Member] \| Stock Option [Member]
Assumptions used in determining the fair value of stock options granted for fixed awards with graded vesting schedules
Vesting period	4 years
Minimum [Member] \| Stock Option [Member]
Assumptions used in determining the fair value of stock options granted for fixed awards with graded vesting schedules
Vesting period	3 years
Long-Term Incentive Plan [Member]
Other information
Total unrecognized stock-based compensation expense, net of estimated forfeitures	6.2
Long-Term Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum Grants Of Awards (in shares)	4,000,000
Total Shareholder Return [Member]
Weighted-Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 30.66
Total Shareholder Return [Member] \| Performance Period Prior To January 01 2014 [Member]
Weighted-Average Grant Date Fair Value
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Period	20 days
Total Shareholder Return [Member] \| Prior to December 31 2016 [Member]
Weighted-Average Grant Date Fair Value
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Period	20 days
Return On Invested Capital [Member]
Weighted-Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 24.72
Restricted Stock [Member]
Weighted-Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 22.64	$ 21.33	$ 19.54	$ 21.47
Other information
Total unrecognized stock-based compensation expense, net of estimated forfeitures	3.2
Weighted average vesting period	2 years 1 month 6 days
Restricted Stock [Member] \| Eligible of the Board of Directors [Member]
Assumptions used in determining the fair value of stock options granted for fixed awards with graded vesting schedules
Vesting period	3 years
Restricted Stock [Member] \| Maximum [Member]
Assumptions used in determining the fair value of stock options granted for fixed awards with graded vesting schedules
Vesting period	5 years
Restricted Stock [Member] \| Minimum [Member]
Assumptions used in determining the fair value of stock options granted for fixed awards with graded vesting schedules
Vesting period	3 years
Performance awards [Member]
Weighted-Average Grant Date Fair Value
Shares earned by the participants	65,237	45,116	30,855
Target awards earned during the performance period (as a percent)	163.30%	133.30%	76.60%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 26.63	$ 21.29	$ 20.51	$ 20.39
Other information
Total unrecognized stock-based compensation expense, net of estimated forfeitures	$ 2.5
Weighted average vesting period	1 year 7 months 6 days
Performance awards [Member] \| Maximum [Member]
Weighted-Average Grant Date Fair Value
Potential Payout As a Percentage of Target Shares	200.00%
Performance awards [Member] \| Minimum [Member]
Weighted-Average Grant Date Fair Value
Potential Payout As a Percentage of Target Shares	0.00%