DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES (Effect of Derivative Instruments on Consolidated Statements of Financial Position) (Details) - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Asset Derivatives		$ 47.3	$ 163.6
Liability Derivatives		(221.0)	(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]	(165.1)	(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]	(144.0)	(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]	(21.1)	(72.3)
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives		47.3	163.6
Liability Derivatives		(55.9)	(51.4)
Derivatives Not Designated as Hedging Instruments [Member] | Other Current Assets [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives		44.1	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		3.2	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]	(52.3)	(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		$ (3.6)	$ (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 of cash collateral held at December 31, 2015.