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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).

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No definition available.

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

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No definition available.

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

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No definition available.

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

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No definition available.

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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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-Section 50
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Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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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.

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

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No definition available.

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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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No definition available.

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Number of non-option equity instruments exercised by participants.

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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).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Stock-Based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other information
Allocated Share-based Compensation Expense	$ 4.8	$ 4.7	$ 3.5
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	$ 0.1
Weighted average vesting period	2 months 12 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	$ 5.7
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
Phantom Stock [Member]
Other information
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	3,804
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 29.57
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	$ 47.24
Total Shareholder Return [Member] \| Performance Period Prior To January 01 2015 [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 2017 [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	$ 30.16
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	$ 24.48	$ 22.64	$ 21.33	$ 19.54
Other information
Total unrecognized stock-based compensation expense, net of estimated forfeitures	$ 2.9
Weighted average vesting period	1 year 7 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	83,236	82,351	76,590
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 29.21	$ 24.46	$ 24.48
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	198,145	220,337	211,716	185,764
Performance awards [Member]
Weighted-Average Grant Date Fair Value
Shares earned by the participants	40,474	65,237	45,116
Target awards earned during the performance period (as a percent)	91.40%	163.30%	133.30%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 32.68	$ 26.63	$ 21.29	$ 20.51
Other information
Total unrecognized stock-based compensation expense, net of estimated forfeitures	$ 2.7
Weighted average vesting period	1 year 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	69,978	85,078	46,106
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 38.70	$ 27.69	$ 24.68
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	143,608	126,803	87,194	74,923
Performance awards [Member] \| Maximum [Member]
Weighted-Average Grant Date Fair Value
Potential Payout As a Percentage of Target Shares	200.00%
Other information
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	143,608
Performance awards [Member] \| Minimum [Member]
Weighted-Average Grant Date Fair Value
Potential Payout As a Percentage of Target Shares	0.00%