DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES (Effect of Derivative Instruments on Consolidated Statements of Income and AOCI) (Details) - Derivatives in Cash Flow Hedging Relationships [Member] - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)		$ (132.5)	$ 55.3	$ (185.8)	$ (85.1)
Amount of Gain (Loss) Reclassified from AOCI to Earnings (Effective Portion)		4.9	(6.1)	12.1	(24.5)
Amount of Gain (Loss) Recognized in Earnings on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	[1]	(7.9)	(61.3)	20.5	(71.7)
Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)		(127.0)	44.1	(169.0)	(93.0)
Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)		(5.5)	11.2	(16.8)	7.9
Interest Expense [Member] | Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from AOCI to Earnings (Effective Portion)		(3.7)	(4.0)	(12.0)	(12.1)
Amount of Gain (Loss) Recognized in Earnings on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	[1]	(7.8)	(62.2)	24.6	(73.2)
Commodity Costs [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from AOCI to Earnings (Effective Portion)		8.6	(2.1)	24.1	(12.4)
Amount of Gain (Loss) Recognized in Earnings on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	[1]	$ (0.1)	$ 0.9	$ (4.1)	$ 1.5

[1] Includes only the ineffective portion of derivatives that are designated as hedging instruments and does not include net gains or losses associated with derivatives that do not qualify for hedge accounting treatment.