Share-Based Compensation - Summary of Grant Date Fair Value of Awards (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Grant date fair value of awards during the period:
Options	$ 244	$ 53	$ 20,315	$ 12,633
Restricted stock	0	18	4,584	3,379
Total	244	71	24,899	16,012
Share-based compensation expense:
Options	1,874	1,076	5,156	3,202
Restricted stock	911	839	2,702	2,412
Total	2,785	1,915	7,858	5,614
Income tax benefit/(deficiency) related to share-based compensation [Abstract]
Options	233	379	964	980
Restricted stock	7	26	462	245
Total	$ 240	$ 405	$ 1,426	$ 1,225