DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES (Effect of Derivative Instruments on Consolidated Statements of Financial Position) (Details) - USD ($) $ in Millions		Mar. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Asset Derivatives		$ 128.1	$ 163.6
Liability Derivatives		(289.7)	(208.9)
Cash collateral held			12.6
Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	[1]	0.0	0.0
Liability Derivatives	[1]	(245.0)	(157.5)
Derivatives Designated as Hedging Instruments [Member] | Accounts Payable and Other [Member] | Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	[1]	0.0	0.0
Liability Derivatives	[1]	(118.3)	(85.2)
Derivatives Designated as Hedging Instruments [Member] | Other Long-term Liabilities [Member] | Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	[1]	0.0	0.0
Liability Derivatives	[1]	(126.7)	(72.3)
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives		128.1	163.6
Liability Derivatives		(44.7)	(51.4)
Derivatives Not Designated as Hedging Instruments [Member] | Other Current Assets [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives		101.9	123.9
Liability Derivatives		0.0	0.0
Derivatives Not Designated as Hedging Instruments [Member] | Other Assets, Net [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives		26.2	39.7
Liability Derivatives		0.0	0.0
Derivatives Not Designated as Hedging Instruments [Member] | Accounts Payable and Other [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	[2]	0.0	0.0
Liability Derivatives	[2]	(30.4)	(33.1)
Derivatives Not Designated as Hedging Instruments [Member] | Other Long-term Liabilities [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives		0.0	0.0
Liability Derivatives		$ (14.3)	$ (18.3)

[1] Includes items currently designated as hedging instruments. Excludes the portion of de-designated hedges which may have a component remaining in AOCI.

[2] Liability derivatives exclude $12.6 million held of cash collateral at December 31, 2015.