Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current Assets
Cash and Cash Equivalents	$ 1,183	$ 1,117
Accounts Receivable, Net	857	947
Commodity Derivative Assets, Current	710	1
Other Current Assets	325	546
Total Current Assets	3,075	2,611
Property, Plant and Equipment
Oil and Gas Properties (Successful Efforts Method of Accounting)	25,599	22,243
Property, Plant and Equipment, Other	630	517
Total Property, Plant and Equipment, Gross	26,229	22,760
Accumulated Depreciation, Depletion and Amortization	(8,086)	(7,035)
Total Property, Plant and Equipment, Net	18,143	15,725
Goodwill	620	627
Other Noncurrent Assets	715	679
Total Assets	22,553	19,642
Current Liabilities
Accounts Payable - Trade	1,578	1,354
Other Current Liabilities	944	988
Total Current Liabilities	2,522	2,342
Long-Term Debt	6,103	4,566
Deferred Income Taxes, Noncurrent	2,516	2,441
Other Noncurrent Liabilities	1,087	1,109
Total Liabilities	12,228	10,458
Shareholders Equity [Abstract]
Preferred Stock - Par Value $1.00 per share; 4 Million Shares Authorized, None Issued	0	0
Common Stock - Par Value $0.01; 500 Million Shares Authorized; 402 Million and 400 Million Shares Issued, Respectively	4	4
Additional Paid in Capital	3,624	3,463
Accumulated Other Comprehensive Loss	(90)	(117)
Treasury Stock, at Cost; 38 Million Shares	(671)	(659)
Retained Earnings	7,458	6,493
Total Shareholders’ Equity	10,325	9,184
Total Liabilities and Shareholders’ Equity	$ 22,553	$ 19,642