CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 55,350	$ 152,995	$ (1,711)
Other comprehensive income (loss):
Foreign currency translation adjustments	(2,760)	7,620	(2,057)
Foreign currency adjustments to net income upon liquidation of investments in foreign entities	183	(488)	0
Other comprehensive (loss) income	(2,577)	7,132	(2,057)
Comprehensive income (loss)	$ 52,773	$ 160,127	$ (3,768)