Earnings Per Share - (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Numerator:
Net loss	$ (10,622)	$ (4,300)
Denominator:
Weighted average common shares outstanding	23,127	22,972
Effect of dilutive securities:
Outstanding common stock equivalents	0	0
Denominator for diluted earnings per share	23,127	22,972
Basic loss per share	$ (0.46)	$ (0.19)
Diluted loss per share	$ (0.46)	$ (0.19)
Excluded outstanding shared-based awards having an anti-dilutive effect	1,316	796

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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