Consolidated Statements of Operations (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Consolidated Statements of Operations [Abstract]
Revenues	$ 3,634,000,000	$ 3,266,000,000	$ 11,373,000,000	$ 10,391,000,000
Expenses:
Operating	1,972,000,000	1,717,000,000	6,510,000,000	5,817,000,000
Selling, general and administrative	721,000,000	645,000,000	2,054,000,000	1,952,000,000
Impairment charges (Note 3)	0	0	0	11,000,000
Depreciation and amortization	113,000,000	116,000,000	343,000,000	354,000,000
Total expenses	2,806,000,000	2,478,000,000	8,907,000,000	8,134,000,000
Operating income (loss)	828,000,000	788,000,000	2,466,000,000	2,257,000,000
Interest expense	(93,000,000)	(94,000,000)	(281,000,000)	(308,000,000)
Interest income	2,000,000	1,000,000	6,000,000	4,000,000
Net loss on early extinguishment of debt	0	(57,000,000)	0	(32,000,000)
Other items, net	7,000,000	(3,000,000)	(2,000,000)	5,000,000
Earnings (loss) from continuing operations before income taxes and equity in earnings (loss) of investee companies	744,000,000	635,000,000	2,189,000,000	1,926,000,000
(Provision) benefit for income taxes	(254,000,000)	(236,000,000)	(744,000,000)	(665,000,000)
Equity in loss of investee companies, net of tax	(21,000,000)	(14,000,000)	(37,000,000)	(30,000,000)
Net earnings (loss) from continuing operations	469,000,000	385,000,000	1,408,000,000	1,231,000,000
Net earnings (loss) from discontinued operations, net of tax (Note 4)	25,000,000	6,000,000	1,000,000	(50,000,000)
Net earnings	$ 494,000,000	$ 391,000,000	$ 1,409,000,000	$ 1,181,000,000
Basic net earnings (loss) per common share:
Basic net earnings (loss) from continuing operations (in dollars per share)	$ 0.78	$ 0.60	$ 2.30	$ 1.91
Basic net earnings (loss) from discontinued operations (in dollars per share)	$ 0.04	$ 0.01	$ 0	$ (0.08)
Basic net earnings (loss) per common share (in dollars per share)	$ 0.82	$ 0.61	$ 2.31	$ 1.83
Diluted net earnings (loss) per common share:
Diluted net earnings (loss) from continuing operations (in dollars per share)	$ 0.76	$ 0.59	$ 2.25	$ 1.86
Diluted net earnings (loss) from discontinued operations (in dollars per share)	$ 0.04	$ 0.01	$ 0	$ (0.08)
Diluted net earnings per common share (in dollars per share)	$ 0.80	$ 0.60	$ 2.25	$ 1.78
Weighted Average Number Of Common Shares Outstanding [Abstract]
Basic weighted average number of common shares outstanding	603	640	611	645
Diluted weighted average number of common shares outstanding	618	656	627	662
Dividends per common share (in dollars per share)	$ 0.12	$ 0.12	$ 0.36	$ 0.32