Stock-Based Compensation (Details 3) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended				1 Months Ended
	Oct. 31, 2011 Employee Stock Purchase Plan employee	Oct. 31, 2010 Employee Stock Purchase Plan employee	Oct. 31, 2009 Employee Stock Purchase Plan employee	Oct. 31, 2011 2011 Employee Stock Purchase Plan	Apr. 30, 2009 Former Employee Stock Purchase Plan
Employee Stock Purchase Plan
Contribution limit as percentage of base compensation (as a percent)				10.00%
Stock purchase price as a percentage of the fair market value on the purchase date (as a percent)				95.00%	85.00%
Discount of the fair market value for purchase of shares of HP's common stock under ESPP (as a percent)					15.00%
ESPP activity
Compensation expense, net of taxes			$ 24
Shares purchased (in shares)	1.75	1.62	6.16
Weighted average purchase price per share (in dollars per share)	$ 25	$ 47	$ 33
Employees eligible to participate (in number of employees)	261,000	251,000	260,000
Employees who participated (in number of employees)	18,000	18,000	49,000