Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (54,197)	$ (397,268)	$ (25,048)	$ (499,938)
Other comprehensive income (loss):
Foreign currency translation adjustment	(123)	368	(594)	40
Unrealized gain on available for sale securities	0	(7)	0	(7)
Amounts reclassified from accumulated other comprehensive loss	0	0	1,183	0
Other comprehensive (loss) income	(123)	361	589	33
Comprehensive loss	$ (54,320)	$ (396,907)	$ (24,459)	$ (499,905)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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