Earnings per Common Share - Details of Earnings Per Share Calculations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings per Common Share
Net income (loss)	$ 5,050	$ 11,872	$ (2,461)	$ (5,671)	$ 3,964	$ (908)	$ (1,002)	$ 1,792	$ 8,789	$ 3,846	$ (22,399)
Weighted average common shares outstanding:
Basic (in shares)									40,050	39,932	39,802
Incremental shares with dilutive effect:
Restricted stock awards (in shares)									86	114
Diluted (in shares)									40,136	40,046	39,802
Basic (in dollars per share)	$ 0.13	$ 0.30	$ (0.06)	$ (0.14)	$ 0.10	$ (0.02)	$ (0.03)	$ 0.04	$ 0.22	$ 0.10	$ (0.56)
Diluted (in dollars per share)	$ 0.13	$ 0.30	$ (0.06)	$ (0.14)	$ 0.10	$ (0.02)	$ (0.03)	$ 0.04	$ 0.22	$ 0.10	$ (0.56)