Discontinued Operations - Balance sheet (Details) - USD ($) $ in Millions	Apr. 30, 2017	Oct. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total current assets of discontinued operations	$ 0	$ 4,243
Total non-current assets of discontinued operations	0	4,923
Total current liabilities of discontinued operations	0	4,182
Total non-current liabilities of discontinued operations	$ 0	4,013
Enterprise Services | Discontinued Operations, Disposed of by Means Other than Sale, Spinoff
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts receivable		3,093
Inventory		34
Other current assets		1,116
Total current assets of discontinued operations		4,243
Property, plant and equipment		3,332
Long-term financing receivables and other non-current assets		1,591
Total non-current assets of discontinued operations		4,923
Notes payable and short-term borrowings		3
Accounts payable		933
Employee compensation and benefits		838
Taxes on earnings		55
Deferred revenue		849
Other accrued liabilities		1,504
Total current liabilities of discontinued operations		4,182
Long-term debt		392
Other non-current liabilities		3,621
Total non-current liabilities of discontinued operations		$ 4,013