Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Millions, except Share data	Sep. 30, 2011	Dec. 31, 2010
Current assets:
Allowance for accounts receivable	$ 3,994	$ 3,939
Stockholders' deficit:
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,800,000,000	1,800,000,000
Common stock, shares outstanding	436,483,900	427,458,800