CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (106,005)	$ (60,867)	$ (124,578)	$ (566,356)
Net unrealized gain (loss) on foreign currency:
Foreign currency translation gain (loss) arising during the period	4,395	(5,971)	9,125	(11,768)
Less: reclassification adjustments for (gain) loss realized in net loss	0	0	0	0
Foreign currency translation gain (loss)	4,395	(5,971)	9,125	(11,768)
OTHER COMPREHENSIVE INCOME (LOSS)	4,395	(5,971)	9,125	(11,768)
COMPREHENSIVE LOSS	$ (101,610)	$ (66,838)	$ (115,453)	$ (578,124)

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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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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