Stock-Based Compensation--Phantom Stock and RSU Activity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Vest date fair value
Aggregate intrinsic value of unvested phantom shares and RSUs outstanding	$ 13,790
Phantom Shares [Member] \| Phantom Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of fair market value of the Company available for share-based awards	2.00%
Maximum individual award as a percentage of shares available for award	5.00%
Award vesting period	5 years
Days from vesting date to cash settlement	120 days
Weighted average grant date fair value (per share)
Unvested and outstanding at beginning of period	$ 17.01	$ 16.87	$ 16.37
Granted	$ 0.00	$ 0.00	$ 0.00
Vested	$ 12.61	$ 16.20	$ 14.38
Forfeited	$ 19.95	$ 17.57	$ 17.18
Unvested and outstanding at end of period	$ 20.18	$ 17.01	$ 16.87
Shares
Unvested and outstanding at beginning of period (in shares)	53,162	84,764	125,768
Granted	0	0	0
Vested	(22,041)	(21,260)	(26,908)
Forfeited	(7,942)	(10,342)	(14,096)
Unvested and outstanding at end of period (in shares)	23,179	53,162	84,764
Vest date fair value
Vest date fair value	212	273	431
Restricted Stock Units (RSU) [Member] \| Restricted Stock Unit Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of fair market value of the Company available for share-based awards	2.00%
Days from vesting date to cash settlement	120 days
Weighted average grant date fair value (per share)
Unvested and outstanding at beginning of period	$ 13.53	$ 17.12	$ 0.00
Granted	$ 8.52	$ 12.45	$ 17.07
Vested	$ 13.96	$ 17.12	$ 0.00
Forfeited	$ 9.85	$ 14.27	$ 16.80
Unvested and outstanding at end of period	$ 9.91	$ 13.53	$ 17.12
Shares
Unvested and outstanding at beginning of period (in shares)	325,297	151,909	0
Granted	504,752	291,253	177,026
Vested	(118,400)	(50,246)	0
Forfeited	(142,489)	(67,619)	(25,117)
Unvested and outstanding at end of period (in shares)	569,160	325,297	151,909
Vest date fair value
Vest date fair value	1,094	626	0
Phantom Stock and RSU [Member] \| Phantom Stock Plan And Restricted Stock Unit Plan [Member]
Vest date fair value
Estimated fair value per share at end of period	$ 3.83
Aggregate intrinsic value of unvested phantom shares and RSUs outstanding	$ 2,269
Maximum [Member] \| Restricted Stock Units (RSU) [Member] \| Restricted Stock Unit Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years

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Share-Based Compensation Arrangement By Share-Based Payment Award, Period From Vesting Date Before Award Is Cash Settled

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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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Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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

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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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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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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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Per share weighted average intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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

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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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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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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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