CONDENSED CONSOLIDATED BALANCE SHEET (Unaudited) (Parenthetical) - $ / shares	Jul. 31, 2016	Oct. 31, 2015
Stockholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	125,000,000	125,000,000
Preferred stock, issued and outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	2,000,000,000	2,000,000,000
Common stock, issued and outstanding (in shares)	613,000,000	611,000,000
Treasury stock at cost, shares (in shares)	289,000,000	279,000,000