Derivative Instruments, Hedging Activities and Fair Value (Details 2) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion		$ 4,963	$ (786)	$ 11,382	$ (3,321)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income - Effective Portion		78	0	80	(3)
Amount of Gain (Loss) Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing		13,087	26,629	24,739	21,254
Foreign currency forward exchange contracts
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion		2,517	77	2,851	97
Amount of Gain (Loss) Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing		0	0	0	0
Foreign currency forward exchange contracts | Cost of services and products sold
Effect of derivative instruments
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income - Effective Portion		78	0	80	(3)
Derivatives Not Designated as Hedging Instruments
Amount of Gain (Loss) Recognized in Income on Derivative	[1]	2,724	(1,126)	(4,510)	(704)
Cross currency interest rate swaps
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion		2,446	(863)	8,531	(3,418)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income - Effective Portion		0	0	0	0
Cross currency interest rate swaps | Cost of services and products sold
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing	[2]	$ 13,087	$ 26,629	$ 24,739	$ 21,254

[1] These gains (losses) offset amounts recognized in cost of services and products sold principally as a result of intercompany or third party foreign currency exposures.

[2] These gains (losses) offset foreign currency fluctuation effects on the debt principal.