Derivative Instruments, Hedging Activities and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Derivative contracts
Derivatives subject to enforceable master netting arrangements, net liability	(100)	$ 0
Derivatives designated as hedging instruments
Derivative contracts
Asset Derivatives	91,443	53,409
Liability Derivatives	17	2,599
Derivatives designated as hedging instruments | Foreign currency forward exchange contracts | Other current assets
Derivative contracts
Asset Derivatives	902	420
Derivatives designated as hedging instruments | Foreign currency forward exchange contracts | Other current liabilities
Derivative contracts
Liability Derivatives	0	0
Derivatives designated as hedging instruments | Cross-currency interest rate swaps | Other assets
Derivative contracts
Asset Derivatives	90,541	52,989
Derivatives designated as hedging instruments | Cross-currency interest rate swaps | Other liabilities
Derivative contracts
Liability Derivatives	17	2,599
Derivatives not designated as hedging instruments | Foreign currency forward exchange contracts | Other current assets
Derivative contracts
Asset Derivatives	5,479	4,065
Derivatives not designated as hedging instruments | Foreign currency forward exchange contracts | Other current liabilities
Derivative contracts
Liability Derivatives	3,334	$ 4,618
Minimum | Derivatives designated as hedging instruments
Derivative contracts
Period over which gains and losses are reclassified to earnings	10 years
Maximum | Derivatives designated as hedging instruments
Derivative contracts
Period over which gains and losses are reclassified to earnings	15 years