Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share
Net (loss) income for basic and diluted (loss) income per share	$ (2,506)	$ 16,733
Shares of common stock and common stock equivalents:
Average common shares used in basic computation	33,106,000	34,268,000
Effect of dilutive securities (in shares)		1,183,000
Average common shares used in diluted computation	33,106,000	35,451,000
(Loss) income per share:
Basic (in dollars per share)	$ (0.08)	$ 0.49
Diluted (in dollars per share)	$ (0.08)	$ 0.47
Anti-dilutive equity awards not included in the detailed earnings per share computation
Equity awards not included in the diluted earnings per share computation	0	0

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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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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