Components of Income (Loss) Before Income Tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income (loss) before income taxes:
Income before income taxes	$ 45,766	$ 61,302	$ 76,134
CANADA
Income (loss) before income taxes:
Foreign	78	(796)	(2,036)
UNITED STATES
Income (loss) before income taxes:
U.S.	25,577	39,356	37,327
Other Countries
Income (loss) before income taxes:
Foreign	$ 20,111	$ 22,742	$ 40,843