Equity Compensation (Schedule of Equity Compensation Performance Shares Activity) (Details) (Performance Shares, USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Performance Shares
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Number of Performance Shares Nonvested at beginning of period	183
Number of performance awards granted	202	183
Number of Performance Shares vested	(37)
Number of Performance Shares forfeited	0
Number of Performance Shares Nonvested at end of period	348
Weighted Average Grant Date Fair Value Nonvested at beginning of period	$ 25.06
Weighted Average Grant Date Fair Value Shares granted	$ 28.79
Weighted Average Grant Date Fair Value Shares vested	$ 25.06
Weighted Average Grant Date Fair Value Shares forfeited	$ 0.00
Weighted Average Grant Date Fair Value Nonvested at end of period	$ 27.22

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The number of performance shares granted to participants.

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No definition available.

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- Definition

The number of performance shares that were forfeited during the reporting period.

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No definition available.

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- Definition

Weighted average fair value as of the grant date of performance shares that were not exercised or put into effect as a result of the occurrence of a terminating event.

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No definition available.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on performance shares.

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No definition available.

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- Definition

The number of non-vested equity based performance shares that validly exist and are outstanding as of the beginning of the period.

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No definition available.

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- Definition

The number of non-vested equity based performance shares that validly exist and are outstanding as of the end of the period.

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No definition available.

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- Definition

The weighted average fair value of nonvested awards on performance shares 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, beginning of period.

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No definition available.

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- Definition

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No definition available.

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- Definition

The number of performance awards that vested during the reporting period.

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No definition available.

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- Definition

The weighted average fair value as of grant date pertaining to performance shares 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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No definition available.

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