Restatement of Quarterly Financial Information (Unaudited) Restatement of the Consolidated Statements of Comprehensive Income (Details) - USD ($)	3 Months Ended								9 Months Ended	12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net (Loss) Income	$ 9,639,000	$ 6,278,000	$ (237,963,000)	$ (311,253,000)	$ (175,293,000)	$ (713,445,000)	$ (54,885,000)	$ (110,956,000)	$ (879,286,000)	$ (533,299,000)	$ (1,054,579,000)	$ 312,908,000
Other Comprehensive (Loss) Income, Net of Tax
Currency translation adjustments						36,912,000			142,248,000	(106,651,000)	191,267,000	(101,539,000)
Defined benefit pension plan adjustments						1,106,000			3,185,000	450,000	14,491,000	2,154,000
Net unrealized (losses) gains on available-for-sale security						(3,848,000)			(7,585,000)	(3,748,000)	(5,948,000)	3,149,000
Net unrealized gains (losses) on derivative instruments:
Unrealized holding gains (losses)						(24,009,000)			(63,999,000)	24,082,000	(55,377,000)	18,733,000
Amounts reclassified from accumulated other comprehensive loss						9,241,000			6,648,000	8,427,000	16,810,000	(16,627,000)
Net unrealized gains (losses) on derivative instruments						(14,768,000)			(57,351,000)	32,509,000	(38,567,000)	2,106,000
Other Comprehensive (Loss) Income, Net of Tax						19,402,000			80,497,000	(77,440,000)	161,243,000	(94,130,000)
Comprehensive (Loss) Income						(694,043,000)			(798,789,000)	(610,739,000)	(893,336,000)	218,778,000
As Previously Reported
Net (Loss) Income	14,913,000		(240,931,000)		(281,283,000)	(603,247,000)	(56,075,000)	(113,231,000)	(772,553,000)	(530,993,000)	(1,053,836,000)	318,022,000
Other Comprehensive (Loss) Income, Net of Tax
Currency translation adjustments						36,912,000			142,248,000
Defined benefit pension plan adjustments						1,106,000			3,185,000
Net unrealized (losses) gains on available-for-sale security						(3,848,000)			(7,585,000)
Net unrealized gains (losses) on derivative instruments:
Unrealized holding gains (losses)						(24,009,000)			(63,999,000)
Amounts reclassified from accumulated other comprehensive loss						9,241,000			6,648,000
Net unrealized gains (losses) on derivative instruments						(14,768,000)			(57,351,000)
Other Comprehensive (Loss) Income, Net of Tax						19,402,000			80,497,000
Comprehensive (Loss) Income						(583,845,000)			(692,056,000)	(608,433,000)	(892,593)	223,892,000
Adjustments
Net (Loss) Income	$ (5,274,000)		$ 2,968,000		$ 105,990,000	(110,198,000)	$ 1,190,000	$ 2,275,000	(106,733,000)	(2,306,000)	(743,000)	(5,114,000)
Other Comprehensive (Loss) Income, Net of Tax
Currency translation adjustments						0			0
Defined benefit pension plan adjustments						0			0
Net unrealized (losses) gains on available-for-sale security						0			0
Net unrealized gains (losses) on derivative instruments:
Unrealized holding gains (losses)						0			0
Amounts reclassified from accumulated other comprehensive loss						0			0
Net unrealized gains (losses) on derivative instruments						0			0
Other Comprehensive (Loss) Income, Net of Tax						0			0
Comprehensive (Loss) Income						$ (110,198,000)			$ (106,733,000)	$ (2,306,000)	$ (743,000)	$ (5,114,000)