Consolidated Statements of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Consolidated Statements of Operations [Abstract]
Revenues	$ 3,188	$ 3,369	$ 6,758	$ 7,132
Expenses:
Operating	1,798	1,892	3,919	4,201
Selling, general and administrative	589	629	1,176	1,238
Depreciation and amortization	71	73	142	147
Total expenses	2,458	2,594	5,237	5,586
Operating income	730	775	1,521	1,546
Interest expense	(94)	(94)	(187)	(188)
Interest income	3	2	6	4
Other items, net	6	(6)	11	(8)
Earnings from continuing operations before income taxes and equity in earnings (loss) of investee companies	645	677	1,351	1,354
(Provision) benefit for income taxes	(217)	(234)	(451)	(452)
Equity in loss of investee companies, net of tax	(10)	(8)	(20)	(17)
Net earnings from continuing operations	418	435	880	885
Net earnings from discontinued operations, net of tax (Note 3)	21	37	27	30
Net earnings	$ 439	$ 472	$ 907	$ 915
Basic net earnings (loss) per common share:
Basic net earnings (loss) from continuing operations (in dollars per share)	$ 0.73	$ 0.71	$ 1.52	$ 1.44
Basic net earnings (loss) from discontinued operations (in dollars per share)	$ 0.04	$ 0.06	$ 0.05	$ 0.05
Basic net earnings (loss) per common share (in dollars per share)	$ 0.77	$ 0.78	$ 1.57	$ 1.49
Diluted net earnings (loss) per common share:
Diluted net earnings (loss) from continuing operations (in dollars per share)	$ 0.72	$ 0.70	$ 1.49	$ 1.40
Diluted net earnings (loss) from discontinued operations (in dollars per share)	$ 0.04	$ 0.06	$ 0.05	$ 0.05
Diluted net earnings per common share (in dollars per share)	$ 0.76	$ 0.76	$ 1.54	$ 1.45
Weighted Average Number Of Common Shares Outstanding [Abstract]
Basic weighted average number of common shares outstanding	570	609	578	615
Diluted weighted average number of common shares outstanding	581	624	590	631
Dividends per common share (in dollars per share)	$ 0.12	$ 0.12	$ 0.24	$ 0.24