Earnings Per Common Share (EPS) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share, Basic and Diluted [Abstract]
Net income, basic									$ 27,523	$ 20,121	$ 23,802
Basic (in shares)									48,805	44,408	44,036
Basic (in dollars per share)	$ 0.14	$ (0.07)	$ 0.19	$ 0.33	$ 0.17	$ 0.02	$ 0.16	$ 0.10	$ 0.56	$ 0.45	$ 0.54
Effect of dilutive stock options and warrants (in shares)									1,296	454	475
Net income, diluted									$ 27,523	$ 20,121	$ 23,802
Diluted (in shares)									50,101	44,862	44,511
Diluted (in dollars per share)	$ 0.13	$ (0.07)	$ 0.19	$ 0.32	$ 0.17	$ 0.02	$ 0.16	$ 0.10	$ 0.55	$ 0.45	$ 0.53
Antidilutive securities excluded from EPS (in shares)									381	727	423