Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share
Total anti-dilutive shares (in shares)	118,525		0		17,864	0
Net income	$ 31,054	$ (15,748)	$ 10,035	$ (6,951)	$ 15,306	$ 3,084
Weighted average shares outstanding - basic	37,958,408		37,299,766		37,749,930	37,151,694
Effect of potentially dilutive restricted stock units and options	367,464		587,793		674,404	737,892
Weighted average shares outstanding - diluted	38,325,872		37,887,559		38,424,334	37,889,586
Basic and diluted:
Basic income per share	$ 0.82		$ 0.27		$ 0.41	$ 0.08
Diluted income per share	$ 0.81		$ 0.26		$ 0.40	$ 0.08