Share-Based Compensation - Summary of Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary of share-based compensation expense
Share-based compensation before income tax benefit	$ 7,190	$ 4,870	$ 10,969
Income tax benefit	(2,241)	(1,227)	(4,079)
Share-based compensation, net of income tax benefit	4,949	3,643	6,890
Performance Unit Incentive Plan (“PUP”)
Summary of share-based compensation expense
Share-based compensation before income tax benefit	3,990	2,260	8,088
Restricted stock
Summary of share-based compensation expense
Share-based compensation before income tax benefit	2,684	2,453	2,594
Restricted stock units
Summary of share-based compensation expense
Share-based compensation before income tax benefit	$ 516	$ 157	$ 287