Income Taxes - Components of the Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
Federal	$ 29,333	$ 26,772	$ 18,288
State	10,930	5,621	3,822
Deferred
Federal	(4,551)	(2,450)	21,493
State	(1,281)	(760)	(269)
Income tax expense	$ 34,431	$ 29,183	$ 43,334