CONSOLIDATED STATEMENT OF SHAREHOLDER'S EQUITY (PARENTHETICALS) (USD $) In Millions	Sep. 30, 2011	Sep. 30, 2010
Statement Of Stockholders Equity Abstract
Tax Provision (Benefit) On Net Unrealized Gain Loss On Available For Sale Marketable Securities ($20 million provision for Sept. 2010 and $16 million benefit for Sept. 2011)	$ (16)	$ 20
Tax Provision (Benefit) On Reclassification Adjustment For Net Gain Loss Included In Net Income ($3 million benefit for Sept. 2010 & $9 million benefit for Sept. 2011)	$ (9)	$ (3)