Earnings per Common Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Earnings Per Share [Abstract]
Net Income	$ 12,176	$ 8,902
Less: Earnings allocated to participating securities	(123)	(132)
Earnings allocated to common shareholders, Basic	12,053	8,770
Weighted average common shares outstanding	39,348	39,195
Basic earnings per common share	$ 0.31	$ 0.22
Dilutive effect of equity awards and warrants	3	103
Earnings allocated to common shareholders, Diluted	$ 12,053	$ 8,770
Weighted average diluted common shares outstanding	39,351	39,298
Diluted earnings per common share	$ 0.31	$ 0.22
Potentially dilutive share options that were not included in the computation of diluted EPS because to do so would be anti-dilutive.	9	46