Consolidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (8,074)	$ (4,791)
Other comprehensive loss:
Unrealized losses on derivative instruments	(22)
Total other comprehensive loss	(22)
Comprehensive loss	$ (8,096)	$ (4,791)