Quarterly Results of Operations (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Ceiling test impairment									$ 0	$ 0	$ 1,488
Income (Loss) from Continuing Operations Attributable to Parent	367	279	(23)	27	(16)	3	107	(21)	650	73	(922)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(7)	(1)	1	257	33	24	4	13	250	74	(262)
Net Income (Loss) Attributable to Parent	360	278	(22)	284	17	27	111	(8)	900	147	(1,184)
Income (Loss) from Continuing Operations, Per Basic Share	$ 2.67	$ 2.04	$ (0.16)	$ 0.19	$ (0.12)	$ (0.13)	$ 0.79	$ (0.15)	$ 4.76	$ 0.39	$ (6.85)
Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share	$ (0.05)	$ 0.00	$ 0.00	$ 1.89	$ 0.25	$ 0.18	$ 0.03	$ 0.09	$ 1.83	$ 0.55	$ (1.95)
Earnings (Loss) Per Share, Basic	$ 2.62	$ 2.04	$ (0.16)	$ 2.08	$ 0.13	$ 0.05	$ 0.82	$ (0.06)	$ 6.59	$ 0.94	$ (8.80)
Income (Loss) from Continuing Operations, Per Diluted Share	$ 2.65	$ 2.01	$ (0.16)	$ 0.19	$ (0.12)	$ (0.13)	$ 0.79	$ (0.15)	$ 4.71	$ 0.39	$ (6.85)
Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share	$ (0.05)	$ 0.00	$ 0.00	$ 1.88	$ 0.25	$ 0.18	$ 0.03	$ 0.09	$ 1.81	$ 0.55	$ (1.95)
Earnings (Loss) Per Share, Diluted	$ 2.60	$ 2.01	$ (0.16)	$ 2.07	$ 0.13	$ 0.05	$ 0.82	$ (0.06)	$ 6.52	$ 0.94	$ (8.80)
Gain on Sale of Malaysia, Before Income Tax									373	0	0
Payments for Repurchase of Preferred Stock and Preference Stock									0	20	0
Continuing Operations [Member]
Oil and Gas Revenue	495	610	612	571	510	505	449	393	2,288	1,857	1,562
Ceiling test impairment									0	0	1,488
Income (loss) from operations	46	167	180	182	126	140	93	91	575	450	(1,354)
Malaysia [Member]
Gain on Sale of Malaysia, Before Income Tax	(15)			388
Gain on Sale of Malaysia, Net of Tax	$ (10)			$ 252