Income Taxes - Income tax provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal	$ 31,398	$ 37,878	$ 9,069
State	9,786	11,584	3,785
Foreign	125	0	0
Total current	41,309	49,462	12,854
Deferred:
Federal	(8,537)	(7,009)	(13,381)
State	(538)	133	(2,941)
Foreign	(4,545)	0	0
Total deferred	(13,620)	(6,876)	(16,322)
Total provision (benefit) for income taxes	$ 27,689	$ 42,586	$ (3,468)