CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net (Loss) Income	$ (603,247)	$ 236,250	$ (772,553)	$ 144,177
Other Comprehensive Income (Loss), Net of Tax:
Currency translation adjustments	36,912	(14,570)	142,248	(18,926)
Defined benefit pension plan adjustments	1,106	2,024	3,185	4,568
Net unrealized losses on available-for-sale security	(3,848)	0	(7,585)	0
Net unrealized losses on derivative instruments:
Unrealized holding (losses) gains	(24,009)	974	(63,999)	642
Reclassification adjustment for realized losses (gains) included in net (loss) income	9,241	(2,157)	6,648	(12,472)
Net unrealized (losses) on derivative instruments	(14,768)	(1,183)	(57,351)	(11,830)
Other Comprehensive Income (Loss), Net of Tax	19,402	(13,729)	80,497	(26,188)
Comprehensive (Loss) Income	$ (583,845)	$ 222,521	$ (692,056)	$ 117,989

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.

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