Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net income per share calculations for basic and diluted methods
Net income available to common stockholders	$ 15,364	$ 25,469
Shares:
Weighted average common shares outstanding	54,662,000	53,277,000
Dilutive effect of outstanding options, warrants and restricted stock units as determined by the application of the treasury stock method (in shares)	251,000	301,000
Weighted average common shares outstanding, as adjusted for diluted earnings per share calculation	54,913,000	53,578,000
Basic earnings per common share (in dollars per share)	$ 0.28	$ 0.48
Diluted earnings per common share (in dollars per share)	$ 0.28	$ 0.48
Stock options
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)	39,965	49,646
Restricted stock unit
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)	204,277	172,571
Warrants
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)	191,278	191,278