Income Taxes - Reconciliation of Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Expected tax expense at federal statutory	$ 428	$ 538	$ 154
State income taxes, net of federal tax effect	54	15	(202)
Revaluation of U.S. deferred income taxes	0	0	(760)
Excess tax benefit from share based compensation and other, net	(1,068)	(380)	(535)
Income tax (benefit) expense	$ (586)	$ 173	$ (1,343)