Changes in Cumulative Other Comprehensive Loss (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016		Mar. 31, 2015
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		$ 867,910
Ending balance		1,000,823		$ 469,172
Tax benefit for unrealized net losses on available-for-sale securities before reclassifications		25		81
Tax benefit for unrealized losses on cash flow hedges		9,075
Tax benefit related to pension and other postretirement benefit plans		(3)		(206)
Tax expense (benefit) for realized gains (losses) on the sale of available-for-sale securities for amounts reclassified from other comprehensive loss		(12)		4
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		$ 33,546	[1]	(56,776)	[2]
Amounts reclassified from other comprehensive loss	[3]
Net change		$ 33,546		(56,776)
Ending balance		(449,083)		(411,160)
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		168	[3]	570	[4]
Net change		168		570
Ending balance		(104,178)		(117,597)
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		(42)	[1]	(132)	[2]
Amounts reclassified from other comprehensive loss		20	[3]	(9)	[4]
Net change		(22)		(141)
Ending balance		(142)		452
Unrealized Net Losses on Cash Flow Hedges [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Amounts recognized in other comprehensive loss	[1]	(14,682)
Net change		(14,682)
Ending balance		(14,682)
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		18,822	[1]	(56,908)	[2]
Amounts reclassified from other comprehensive loss		188	[3]	561	[4]
Net change		19,010		(56,347)
Ending balance		$ (568,085)		$ (528,305)

[1] Net of taxes of $25 for unrealized net losses on available-for-sale securities and $9,075 for unrealized net losses on cash flow hedges.

[2] Net of taxes of $81 for unrealized net losses on available-for-sale securities.

[3] Net of taxes of $(3) for pension and other postretirement benefit adjustments and $(12) for realized losses on the sale of available-for-sale securities.

[4] Net of taxes of $(206) for pension and other postretirement benefit adjustments and $4 for realized gains on the sale of available-for-sale securities.