CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
OPERATING ACTIVITIES
Net income (loss)	$ (41.8)	$ 176.1
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	489.9	504.0
Deferred income taxes	15.8	121.0
Impairment	3.5	0.2
Equity-based compensation	13.4	13.2
Amortization of debt issuance costs and discounts	3.4	3.1
Net (gain) loss from asset sales	198.6	(100.2)
Income from unconsolidated affiliates	(3.4)	(2.9)
Distributions from unconsolidated affiliates and other	6.3	4.1
Unrealized loss on derivative contracts	98.2	1.4
Changes in operating assets and liabilities	76.4	(222.1)
Net Cash Provided by Operating Activities	860.3	497.9
INVESTING ACTIVITIES
Property acquisitions	(949.4)	(22.0)
Property, plant and equipment, including dry exploratory well expense	(779.0)	(719.9)
Proceeds from disposition of assets	706.3	143.0
Acquisition deposit held in escrow	50.0	0
Net Cash Used in Investing Activities	(972.1)	(598.9)
FINANCING ACTIVITIES
Checks outstanding in excess of cash balances	(85.2)	55.8
Long-term debt issued	300.0	0
Long-term debt issuance costs paid	(1.1)	0
Proceeds from credit facility	3,151.0	1,601.0
Repayments of credit facility	(2,538.0)	(1,402.5)
Treasury stock repurchases	(5.5)	(7.5)
Other capital contributions	4.1	2.9
Dividends paid	(7.3)	(7.2)
Excess tax (provisions) benefit on equity-based compensation	(0.6)	1.3
Distribution to noncontrolling interest	(15.2)	(3.1)
Net Cash Provided by Financing Activities	802.2	240.7
Change in cash and cash equivalents	690.4	139.7
Beginning cash and cash equivalents	11.9	0
Ending cash and cash equivalents	702.3	139.7
Supplemental Disclosures:
Cash paid for interest, net of capitalized interest	84.9	76.7
Cash paid for income taxes	0.2	41.5
Non-cash investing activities
Change in capital expenditure accrual balance	$ 26.3	$ 2.8