Debt (Long-Term Debt) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Total long-term debt	$ 6,045	$ 5,385
Less current portion	619	265
Long-term portion	5,426	5,120
Notes and Debentures [Member]
Weighted-average interest rate	5.76%
Maturities start date	2012
Maturities end date	2046
Total long-term debt	4,984	4,286
Dealer Remarketable Securities [Member]
Weighted-average interest rate	4.03%
Maturities start date	2012
Maturities end date	2016
Total long-term debt	200	200
Industrial Development Revenue Bonds [Member]
Weighted-average interest rate	0.13%
Maturities start date	2014
Maturities end date	2037
Total long-term debt	280	280
Bank Loans And Other Financings In Various Currencies [Member]
Weighted-average interest rate	2.70%
Maturities start date	2012
Maturities end date	2045
Total long-term debt	$ 581	$ 619