Consolidated Statements of Equity (USD $) In Millions, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Noncontrolling Interests [Member]
Beginning Balance at Dec. 31, 2011	$ 6,733	$ 1	$ 5,063	$ (3,616)	$ 5,650	$ (454)	$ 89
Beginning Balance, Shares at Dec. 31, 2011		99,000,000.0
Class of Stock [Line Items]
Net income	794				784		10
Other comprehensive income (loss)	(96)					(96)
Distributions to noncontrolling interests	(10)						(10)
Cash dividends declared	(196)				(196)
Shares issued:
Employee savings plans	141		141
Employee savings plans, Shares		2,100,000
Exercise of stock options	19		19
Exercise of stock options, Shares		400,000
Employee stock purchase plan	39		39
Employee stock purchase plan, Shares		700,000
Stock-based compensation expense	60		60
Contribution received from the spin-off of Engility	335				335
Spin-off of Engility	(1,411)				(1,398)		(13)
Treasury stock purchased	(872)			(872)
Treasury stock purchased, Shares		(12,100,000)
Other	(9)		(9)
Other, Shares		300,000
Ending Balance at Dec. 31, 2012	5,527	1	5,313	(4,488)	5,175	(550)	76
Ending Balance, Shares at Dec. 31, 2012		90,400,000.0
Class of Stock [Line Items]
Net income	760				751		9
Other comprehensive income (loss)	440					440
Distributions to noncontrolling interests	(10)						(10)
Cash dividends declared	(201)				(201)
Shares issued:
Employee savings plans	121		121
Employee savings plans, Shares		1,500,000
Exercise of stock options	128		128
Exercise of stock options, Shares		1,800,000
Employee stock purchase plan	36		36
Employee stock purchase plan, Shares		500,000
Stock-based compensation expense	59		59
Treasury stock purchased	(800)			(800)
Treasury stock purchased, Shares		(8,700,000)
Other	(4)		(5)		1
Other, Shares		300,000
Ending Balance at Dec. 31, 2013	6,056	1	5,652	(5,288)	5,726	(110)	75
Ending Balance, Shares at Dec. 31, 2013		85,800,000.0
Class of Stock [Line Items]
Net income	677				664		13
Other comprehensive income (loss)	(474)					(474)
Distributions to noncontrolling interests	(13)						(13)
Cash dividends declared	(209)				(209)
Shares issued:
Employee savings plans	130		130
Employee savings plans, Shares		1,200,000
Exercise of stock options	109		109
Exercise of stock options, Shares	1,183,400	1,200,000
Employee stock purchase plan	35		35
Employee stock purchase plan, Shares		300,000
Stock-based compensation expense	52		52
Treasury stock purchased	(823)			(823)
Treasury stock purchased, Shares		(6,900,000)
Retirement of Convertible Contingent Debt Securities	(161)		(161)
Other	(19)		(19)
Other, Shares		400,000
Ending Balance at Dec. 31, 2014	$ 5,360	$ 1	$ 5,798	$ (6,111)	$ 6,181	$ (584)	$ 75
Ending Balance, Shares at Dec. 31, 2014		82,000,000.0