Changes in Cumulative Other Comprehensive Loss (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2016		Jun. 30, 2015
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		$ 867,910
Ending balance		1,246,629		$ 757,342
Tax expense for unrealized net gains on available-for-sale securities before reclassifications		(282)		(34)
Tax benefit for unrealized losses on cash flow hedges		66,721
Tax benefit related to pension and other postretirement benefit plans		(45)		(699)
Tax expense (benefit) for realized gains (losses) on the sale of available-for-sale securities for amounts reclassified from other comprehensive loss		(78)		33
Foreign Currency Translation Adjustments [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		(482,629)		(354,384)
Amounts recognized in other comprehensive loss		31,935	[1]	(45,554)	[2]
Amounts reclassified from other comprehensive loss	[3]
Net change		31,935		(45,554)
Ending balance		(450,694)		(399,938)
Pension and Other Postretirement Benefit Adjustments [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		(104,346)		(118,167)
Amounts reclassified from other comprehensive loss		439	[3]	853	[4]
Net change		439		853
Ending balance		(103,907)		(117,314)
Unrealized Net (Losses) Gains on Available-for-Sale Securities [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		(120)		593
Amounts recognized in other comprehensive loss		455	[1]	52	[2]
Amounts reclassified from other comprehensive loss		125	[3]	(55)	[4]
Net change		580		(3)
Ending balance		460		590
Unrealized Net Losses on Cash Flow Hedges [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Amounts recognized in other comprehensive loss	[1]	(107,948)
Net change		(107,948)
Ending balance		(107,948)
Total Cumulative Other Comprehensive (Loss) Income [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		(587,095)		(471,958)
Amounts recognized in other comprehensive loss		(75,558)	[1]	(45,502)	[2]
Amounts reclassified from other comprehensive loss		564	[3]	798	[4]
Net change		(74,994)		(44,704)
Ending balance		$ (662,089)		$ (516,662)

[1] Net of taxes of $(282) for unrealized net gains on available-for-sale securities and $66,721 for unrealized net losses on cash flow hedges.

[2] Net of taxes of $(34) for unrealized net gains on available-for-sale securities.

[3] Net of taxes of $(45) for pension and other postretirement benefit adjustments and $(78) for realized losses on the sale of available-for-sale securities.

[4] Net of taxes of $(699) for pension and other postretirement benefit adjustments and $33 for realized gains on the sale of available-for-sale securities.