Consolidated Statements of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Consolidated Statements of Operations [Abstract]
Revenues	$ 3,856	$ 4,040
Expenses:
Operating	2,284	2,474
Selling, general and administrative	642	650
Depreciation and amortization	112	116
Total expenses	3,038	3,240
Operating income	818	800
Interest expense	(106)	(95)
Interest income	3	2
Other items, net	5	(2)
Earnings from continuing operations before income taxes and equity in loss of investee companies	720	705
(Provision) benefit for income taxes	(242)	(234)
Equity in loss of investee companies, net of tax	(10)	(8)
Net earnings from continuing operations	468	463
Net loss discontinued operations, net of tax	0	(20)
Net earnings	$ 468	$ 443
Basic net earnings (loss) per common share:
Basic net earnings (loss) from continuing operations (in dollars per share)	$ 0.80	$ 0.75
Basic net earnings (loss) from discontinued operations (in dollars per share)	$ 0	$ (0.03)
Basic net earnings (loss) per common share (in dollars per share)	$ 0.80	$ 0.71
Diluted net earnings (loss) per common share:
Diluted net earnings (loss) from continuing operations (in dollars per share)	$ 0.78	$ 0.73
Diluted net earnings (loss) from discontinued operations (in dollars per share)	$ 0	$ (0.03)
Diluted net earnings per common share (in dollars per share)	$ 0.78	$ 0.69
Weighted Average Number Of Common Shares Outstanding [Abstract]
Basic weighted average number of common shares outstanding	585	621
Diluted weighted average number of common shares outstanding	600	638
Dividends per common share (in dollars per share)	$ 0.12	$ 0.12