Earnings Per Share - Components of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Net income	$ 9,865	$ 1,873	$ 13,828	$ 4,611
Less: income allocated to participating securities	(5)	(2)	(8)	(7)
Net income attributable to common stockholders	$ 9,860	$ 1,871	$ 13,820	$ 4,604
Weighted average common shares outstanding - basic (in shares)	46,442,327	45,602,061	46,334,499	45,564,059
Dilutive effect of stock options, RSUs and RSAs (in shares)	2,558,226	1,921,126	2,572,313	1,841,452
Weighted average common shares outstanding - diluted (in shares)	49,000,553	47,523,187	48,906,812	47,405,511
Net income per share:
Basic (in dollars per share)	$ 0.21	$ 0.04	$ 0.30	$ 0.10
Diluted (in dollars per share)	$ 0.20	$ 0.04	$ 0.28	$ 0.10