Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net income per share calculations for basic and diluted methods
Net income available to common stockholders (in dollars)	$ 9,755	$ 8,004	$ 17,334	$ 15,709
Shares:
Weighted average common shares outstanding	87,006,000	86,895,000	86,982,000	86,880,000
Dilutive effect of outstanding options, warrants and restricted stock units as determined by the application of the treasury stock method (in shares)	557,000	368,000	546,000	365,000
Weighted average common shares outstanding, as adjusted for diluted earnings per share calculation	87,563,000	87,263,000	87,528,000	87,245,000
Basic earnings per common share (in dollars per share)	$ 0.11	$ 0.09	$ 0.20	$ 0.18
Diluted earnings per common share (in dollars per share)	$ 0.11	$ 0.09	$ 0.20	$ 0.18
Stock options
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)			259,756	476,230
Warrants
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)			573,833	573,833
RSU
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)			380,531	353,976