Restructuring Charges (Details) (USD $)	3 Months Ended		6 Months Ended			1 Months Ended	3 Months Ended	6 Months Ended		1 Months Ended	3 Months Ended	6 Months Ended	1 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	1 Months Ended	3 Months Ended	6 Months Ended		1 Months Ended	6 Months Ended	1 Months Ended	3 Months Ended	6 Months Ended		1 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2013	Apr. 30, 2012	Oct. 31, 2012	May 31, 2012 Fiscal 2012 Restructuring Plan position	Apr. 30, 2013 Fiscal 2012 Restructuring Plan position	Apr. 30, 2013 Fiscal 2012 Restructuring Plan position	May 23, 2012 Fiscal 2012 Restructuring Plan	May 31, 2012 Fiscal 2012 Restructuring Plan Severance and EER	Apr. 30, 2013 Fiscal 2012 Restructuring Plan Severance and EER	Apr. 30, 2013 Fiscal 2012 Restructuring Plan Severance and EER	May 31, 2012 Fiscal 2012 Restructuring Plan Infrastructure and other items	Apr. 30, 2013 Fiscal 2012 Restructuring Plan Infrastructure and other items	Apr. 30, 2013 Fiscal 2012 Restructuring Plan Infrastructure and other items	Apr. 30, 2013 Fiscal 2010 Acquisitions	Apr. 30, 2013 Fiscal 2010 Acquisitions	Apr. 30, 2013 Fiscal 2010 Enterprise Services Business Restructuring Plan	Apr. 30, 2013 Fiscal 2010 Enterprise Services Business Restructuring Plan	Jun. 30, 2010 Fiscal 2010 Enterprise Services Business Restructuring Plan Severance and workforce reductions	Apr. 30, 2013 Fiscal 2010 Enterprise Services Business Restructuring Plan Severance and workforce reductions	Apr. 30, 2013 Fiscal 2010 Enterprise Services Business Restructuring Plan Severance and workforce reductions	Oct. 31, 2012 Fiscal 2010 Enterprise Services Business Restructuring Plan Severance and workforce reductions position	Oct. 31, 2012 Fiscal 2010 Enterprise Services Business Restructuring Plan Severance and workforce reductions U.S. Defined Benefit Plans position	Apr. 30, 2013 Fiscal 2010 Enterprise Services Business Restructuring Plan Infrastructure	Aug. 31, 2008 Fiscal 2008 HP/EDS Restructuring Plan	Apr. 30, 2013 Fiscal 2008 HP/EDS Restructuring Plan	Apr. 30, 2013 Fiscal 2008 HP/EDS Restructuring Plan	Aug. 26, 2008 Fiscal 2008 HP/EDS Restructuring Plan	Aug. 31, 2008 Fiscal 2008 HP/EDS Restructuring Plan Severance and workforce reductions position	Apr. 30, 2013 Fiscal 2008 HP/EDS Restructuring Plan Severance and workforce reductions	Apr. 30, 2013 Fiscal 2008 HP/EDS Restructuring Plan Infrastructure	Apr. 30, 2013 Fiscal 2008 HP/EDS Restructuring Plan Infrastructure
Restructuring and related costs
Expected positions to be eliminated						29,000																		8,200						25,000
Positions eliminated							18,800	18,800															8,200
Variance of expected headcount reductions (as a percent)									15.00%
Charges	$ 408,000,000	$ 53,000,000	$ 538,000,000	$ 93,000,000			$ 433,000,000	$ 723,000,000			$ 409,000,000	$ 665,000,000		$ 24,000,000	$ 58,000,000	$ (10,000,000)	$ (10,000,000)	$ (14,000,000)	$ (171,000,000)		$ (14,000,000)	$ (171,000,000)					$ (1,000,000)	$ (4,000,000)				$ (1,000,000)	$ (4,000,000)
Costs reflected in purchase price of Electronic Data Systems Corporation ("EDS")																													1,500,000,000
Amount of restructuring charges anticipated																	0		0
Restructuring Reserve
Balance at the beginning of the period			1,027,000,000					608,000,000				597,000,000			11,000,000		10,000,000		228,000,000			227,000,000			1,000,000			181,000,000					181,000,000
Charges	408,000,000	53,000,000	538,000,000	93,000,000			433,000,000	723,000,000			409,000,000	665,000,000		24,000,000	58,000,000	(10,000,000)	(10,000,000)	(14,000,000)	(171,000,000)		(14,000,000)	(171,000,000)					(1,000,000)	(4,000,000)				(1,000,000)	(4,000,000)
Cash payments			(402,000,000)					(342,000,000)				(300,000,000)			(42,000,000)				(31,000,000)			(31,000,000)						(29,000,000)					(29,000,000)
Other adjustments and non-cash settlements			4,000,000					3,000,000				3,000,000							2,000,000			2,000,000						(1,000,000)					(1,000,000)
Balance at the end of the period	1,167,000,000		1,167,000,000				992,000,000	992,000,000			965,000,000	965,000,000		27,000,000	27,000,000			28,000,000	28,000,000		27,000,000	27,000,000			1,000,000		147,000,000	147,000,000				147,000,000	147,000,000
Total costs and adjustments to date			6,991,000,000					2,813,000,000				2,650,000,000			163,000,000		91,000,000		821,000,000			452,000,000			369,000,000			3,266,000,000			2,195,000,000		1,071,000,000
Total expected costs and adjustments			7,796,000,000					3,609,000,000				3,027,000,000			582,000,000		91,000,000		821,000,000			452,000,000			369,000,000			3,275,000,000			2,195,000,000		1,080,000,000
Short-term portion of restructuring reserve, recorded in Accrued restructuring	1,063,000,000		1,063,000,000		771,000,000
Long-term portion of restructuring reserve, recorded in Other liabilities	104,000,000		104,000,000		256,000,000
Expected cost of the plan						$ 3,600,000,000				$ 3,000,000,000			$ 600,000,000							$ 821,000,000						$ 3,300,000,000