Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (29,722)	$ (24,231)
Other comprehensive loss:
Unrealized loss on cash flow hedge	(93)	62
Comprehensive loss	$ (29,815)	$ (24,169)