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)	$ 28,009	$ 12,089
Other comprehensive income (loss), net of tax:
Foreign currency translation	1	(2)
Total other comprehensive income (loss), net of tax	1	(2)
Comprehensive income (loss)	$ 28,010	$ 12,087