Consolidated Statements of Cash Flows (unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash Flows From Operating Activities
Net Income	$ 261	$ 263
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Depreciation, Depletion and Amortization	367	312
Deferred Income Taxes	52	32
Dividends (Income) from Equity Method Investees, Net	(35)	(29)
Unrealized Loss on Commodity Derivative Instruments	79	73
Gain on Divestitures	(53)	0
Stock Based Compensation	18	16
Other Adjustments for Noncash Items Included in Income	25	15
Changes in Operating Assets and Liabilities
Increase in Accounts Receivable	(56)	(135)
(Increase) Decrease in Other Current Assets	20	(5)
Increase in Accounts Payable	82	190
Decrease in Other Current Liabilities	(48)	(26)
Other Operating Assets and Liabilities, Net	(7)	35
Net Cash Provided by Operating Activities	705	741
Cash Flows From Investing Activities
Additions to Property, Plant and Equipment	(806)	(1,018)
Additions to Equity Method Investments	(20)	(14)
Proceeds from Divestitures	76	0
Other	2	0
Net Cash Used in Investing Activities	(748)	(1,032)
Cash Flows From Financing Activities
Exercise of Stock Options	22	27
Excess Tax Benefits from Stock-Based Awards	9	12
Dividends Paid, Common Stock	(44)	(39)
Purchase of Treasury Stock	(14)	(13)
Repayment of Capital Lease Obligation	(12)	(8)
Net Cash Used In Financing Activities	(39)	(21)
Decrease in Cash and Cash Equivalents	(82)	(312)
Cash and Cash Equivalents at Beginning of Period	1,387	1,455
Cash and Cash Equivalents at End of Period	$ 1,305	$ 1,143