Changes in Cumulative Other Comprehensive Loss (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2015		Sep. 30, 2014
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		$ (471,958)		$ (321,044)
Other comprehensive (loss) income before reclassifications		(99,677)	[1]	(52,160)	[2]
Amounts reclassified from other comprehensive (loss) income		2,218	[3]	1,418	[4]
Net other comprehensive (loss) income		(97,459)		(50,742)
Ending balance		(569,417)		(371,786)
Tax expense (benefit) for unrealized net gains (losses) on available-for-sale securities before reclassifications		(966)		387
Tax expense (benefit) for net actuarial losses and prior service costs recognized for employee benefit plans for amounts reclassified from other comprehensive loss		(593)		(556)
Tax expense (benefit) for realized gains (losses) on the sale of available-for-sale securities for amounts reclassified from other comprehensive loss		(303)		59
Tax expense (benefit) for net actuarial losses and prior service costs recognized for employee benefit plans before reclassifications				244
Foreign Currency Translation Adjustments [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		(354,384)		(250,942)
Other comprehensive (loss) income before reclassifications		$ (98,120)	[1]	(52,206)	[2]
Amounts reclassified from other comprehensive (loss) income	[3]
Net other comprehensive (loss) income		$ (98,120)		(52,206)
Ending balance		(452,504)		(303,148)
Net Actuarial (Losses) Gains and Prior Service Costs Recognized for Employee Benefit Plans [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		(118,167)		(70,611)
Other comprehensive (loss) income before reclassifications	[2]			(570)
Amounts reclassified from other comprehensive (loss) income		1,734	[3]	1,512	[4]
Net other comprehensive (loss) income		1,734		942
Ending balance		(116,433)		(69,669)
Unrealized Net Gains (Losses) on Available-for-Sale Securities [Member]
Changes in Net Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance		593		509
Other comprehensive (loss) income before reclassifications		(1,557)	[1]	616	[2]
Amounts reclassified from other comprehensive (loss) income		484	[3]	(94)	[4]
Net other comprehensive (loss) income		(1,073)		522
Ending balance		$ (480)		$ 1,031

[1] Net of taxes of $966 for unrealized net losses on available-for-sale securities.

[2] Net of taxes of $244 for net actuarial losses and prior service costs recognized for employee benefit plans and $(387) for unrealized net gains on available-for-sale securities.

[3] Net of taxes of $(593) for net actuarial losses and prior service costs recognized for employee benefit plans and $(303) for realized losses on the sale of available-for-sale securities.

[4] Net of taxes of $(556) for net actuarial losses and prior service costs recognized for employee benefit plans and $59 for realized gains on the sale of available-for-sale securities.