Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)		$ 6,709	$ (4,751)
Other comprehensive income (loss), net of tax
Currency translation adjustment	[1]	(142)	1,424
Comprehensive income (loss)		6,567	(3,327)
Net income attributable to non-controlling interest, net of tax		4	96
Total comprehensive income		$ 6,563	$ (3,423)

[1] No other comprehensive income (loss) is attributable to non-controlling interests.