FAIR VALUE MEASUREMENTS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended										3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Recurring Level 1	Dec. 31, 2012 Recurring Level 1	Dec. 31, 2013 Recurring Level 2	Dec. 31, 2012 Recurring Level 2	Dec. 31, 2013 Recurring Netting and Collateral	Dec. 31, 2012 Recurring Netting and Collateral	Dec. 31, 2013 Recurring Total Fair Value	Dec. 31, 2012 Recurring Total Fair Value	Dec. 31, 2013 Non recurring	Dec. 31, 2012 Non recurring	Dec. 31, 2012 Non recurring Minimum
Assets:
Commodity derivatives			$ 185	$ 107	$ 195	$ 312	$ (329)	$ (301)	$ 51	$ 118
Liabilities:
Commodity derivatives			199	99	223	398	(364)	(371)	58	126
Asset impairments and related items	$ 621.0	$ 1,751.0									$ 0.6	$ 1,700.0
Percentage of pre-tax impairment charges related to natural gas properties													90.00%
Average period over which natural gas properties were acquired													5 years