Income Taxes - Income Tax Expense Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal	$ 14,645	$ 14,123	$ 9,700
State	5,198	5,698	4,035
Foreign	1,736	1,537	2,418
Total current	21,579	21,358	16,153
Deferred:
Federal	(1,721)	320	4,072
State	314	(25)	1,452
Foreign	(458)	(418)	(250)
Total deferred	(1,865)	(123)	5,274
Income tax expense	$ 19,714	$ 21,235	$ 21,427