Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Revenues	$ 3,849	$ 3,500
Cost and expenses:
Operating	2,356	2,142
Selling, general and administrative	617	588
Depreciation and amortization	64	68
Other operating items, net	(9)	(19)
Total costs and expenses	3,028	2,779
Operating income (loss)	821	721
Interest expense	(100)	(93)
Interest income	7	5
Other items, net	(3)	(23)
Earnings before income taxes and equity in loss of investee companies	725	610
Provision for income taxes	(231)	(203)
Equity in loss of investee companies, net of tax	(21)	(13)
Net earnings	$ 473	$ 394
Basic net earnings per common share (in dollars per share)	$ 1.03	$ 0.79
Diluted net earnings per common share (in dollars per share)	$ 1.02	$ 0.78
Weighted average number of common shares outstanding:
Basic weighted average number of common shares outstanding	459	498
Diluted weighted average number of common shares outstanding	464	506
Dividends per common share (in dollars per share)	$ 0.15	$ 0.15