Derivative Instruments, Hedging Activities and Fair Value (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Designated as hedging instrument
Derivative contracts
Asset Derivatives	$ 70,907	$ 53,409
Liability Derivatives	$ 1,002	2,599
Designated as hedging instrument | Minimum
Derivative contracts
Period over which gains and losses are reclassified to earnings	10 years
Designated as hedging instrument | Maximum
Derivative contracts
Period over which gains and losses are reclassified to earnings	15 years
Designated as hedging instrument | Foreign currency forward exchange contracts | Other current assets
Derivative contracts
Asset Derivatives	$ 472	420
Designated as hedging instrument | Foreign currency forward exchange contracts | Other current liabilities
Derivative contracts
Liability Derivatives	0	0
Designated as hedging instrument | Cross currency interest rate swaps | Other assets
Derivative contracts
Asset Derivatives	70,435	52,989
Designated as hedging instrument | Cross currency interest rate swaps | Noncurrent liabilities
Derivative contracts
Liability Derivatives	1,002	2,599
Derivatives Not Designated as Hedging Instruments | Foreign currency forward exchange contracts | Other current assets
Derivative contracts
Asset Derivatives	1,983	4,065
Derivatives Not Designated as Hedging Instruments | Foreign currency forward exchange contracts | Other current liabilities
Derivative contracts
Liability Derivatives	$ 4,504	$ 4,618