CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net loss	$ (231,156)	$ (162,602)	$ (274,158)
Other comprehensive income (loss):
Unrealized gains on marketable securities, net of tax of $4,586	6,821		(20)
Cumulative translation adjustment, net of tax of $0	393	214	(40)
Defined benefit pension obligation, net of tax of $0	806	(2,864)	(1,495)
Other comprehensive income (loss)	8,020	(2,650)	(1,555)
Comprehensive loss	$ (223,136)	$ (165,252)	$ (275,713)