DERIVATIVE CONTRACTS AND COLLATERALIZED INDEBTEDNESS, Location of Assets and Liabilities with the Consolidated Balance Sheets (Details) - Designated as Hedging Instruments - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Derivative Instruments, Fair Value [Abstract]
Asset Derivatives	$ 30,814	$ 7,317
Liability Derivatives	36,495	102,217
Prepaid forward contracts | Current derivative contracts
Derivative Instruments, Fair Value [Abstract]
Asset Derivatives	453	0
Liability Derivatives	36,495	93,010
Prepaid forward contracts | Long-term derivative contracts
Derivative Instruments, Fair Value [Abstract]
Asset Derivatives	30,361	7,317
Liability Derivatives	$ 0	$ 9,207