Income Taxes - Provision (benefit) for income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal	$ 11,000	$ 31,200	$ 33,600
State	3,100	6,500	6,400
Foreign	1,300	1,900	2,100
Current Income Tax Expense	15,400	39,600	42,100
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal	(17,300)	(3,800)	(7,800)
State	(2,700)	(1,700)	(4,000)
Deferred income tax expense (benefit)	(20,049)	(5,494)	(11,847)
(Benefit) provision for income taxes	$ (4,568)	$ 34,127	$ 30,254