CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowances	$ 332	$ 300
Common stock, par value (in dollars per share)	$ 0.000001	$ 0.000001
Common stock, shares authorized	2,400,000,000	2,400,000,000
Common stock, shares issued	1,111,606,087	1,133,391,371