Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data	Sep. 30, 2011	Dec. 31, 2010
Accounts receivable, allowance for doubtful accounts	$ 293	$ 304
Other intangible assets, accumulated amortization	153	157
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,200,000,000	1,200,000,000
Common stock, shares issued	807,093,084	804,894,313
Common stock, shares outstanding	770,260,308	787,607,240
Treasury stock, shares	36,832,776	17,287,073
Variable Interest Entity [Line Items]
Non-recourse debt - current, balance at variable interest entities	2,163	2,567
Non-recourse debt - noncurrent, balance at variable interest entities	12,523	12,371
Consolidated Variable Interest Entities [Member]
Variable Interest Entity [Line Items]
Non-recourse debt - current, balance at variable interest entities	269	1,150
Non-recourse debt - noncurrent, balance at variable interest entities	$ 2,168	$ 2,199