Legal Proceedings, Commitments, And Contingencies (Details) (USD $)	12 Months Ended									12 Months Ended		12 Months Ended
	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 N Y Metropolitan Transportation Authority [Member]	Apr. 24, 2009 N Y Metropolitan Transportation Authority [Member]	Dec. 31, 2011 Environmental Matters [Member]	Dec. 31, 2010 Environmental Matters [Member]	Dec. 31, 2011 Standby Letters Of Credit [Member]	Dec. 31, 2010 Standby Letters Of Credit [Member]	Dec. 31, 2011 United Launch Alliance [Member]	Dec. 31, 2010 United Launch Alliance [Member]	Dec. 31, 2010 Third Party Guarantees [Member]	Dec. 31, 2011 Third Party Guarantees [Member]	Dec. 31, 2011 Other Liabilities [Member]	Dec. 31, 2010 Other Liabilities [Member]	Dec. 31, 2011 Other Assets [Member] Environmental Matters [Member]	Dec. 31, 2010 Other Assets [Member] Environmental Matters [Member]
Loss Contingencies [Line Items]
Contract value					$ 323,000,000
Contract payments received to date				241,000,000
Liabilities recorded relative to environmental matters						932,000,000	935,000,000							814,000,000	807,000,000
Environmental costs eligible for future recovery						808,000,000	810,000,000									706,000,000	699,000,000
Time period environmental costs and recovery of environmental costs are projected over	20
Percentage of expenditures that are reimbursed for certain remediation activities	50.00%
Total rental expense under operating leases	347,000,000	399,000,000	370,000,000
Future minimum lease commitments, total	1,000,000,000
Future minimum lease commitments, due in 2012	264,000,000
Future minimum lease commitments, due in 2013	200,000,000
Future minimum lease commitments, due in 2014	139,000,000
Future minimum lease commitments, due in 2015	97,000,000
Future minimum lease commitments, due in 2016	71,000,000
Future minimum lease commitments, due in later years	246,000,000
Outstanding letters of credit, surety bonds and third-party guarantees								3,900,000,000	4,200,000,000
Third-party guarantees outstanding												1,000,000,000	907,000,000
Percentage of total guarantees that relate to guarantees of contractual performance of joint ventures												85.00%
Ownership interest in affiliated entity										50.00%
Number of years the difference between book value and underlying equity in equity method investment is being recognized ratably										10
Dividends that are subject to contingency										352,000,000
Revolving line of credit										400,000,000
Amount of net assets exceeded book value of investment recognizing ratably over 10 years										395,000,000
Total equity method investment	$ 697,000,000	$ 671,000,000								$ 574,000,000	$ 513,000,000