| **Restructuring and Impairments (Tables)**                           | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Restructuring and Related Activities [Abstract]**                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| Schedule of Restructuring Reserve by Type of Cost [Table Text Block] | The following tables summarize the activity in the restructuring liability, which includes amounts related to discontinued operations and excludes pension and other postretirement contractual termination benefits:(in millions)Balance at October 31, 2015 Additions Payments Adjustments Balance at April 30, 2016Employee termination charges$62 $6 $(49) $— $19Lease vacancy5 — (3) — 2Other1 — — — 1Restructuring liability$68 $6 $(52) $— $22(in millions)Balance atOctober 31, 2014 Additions Payments Adjustments Balance at April 30, 2015Employee termination charges$8 $7 $(4) $(1) $10Lease vacancy11 — (4) — 7Other1 — — — 1Restructuring liability$20 $7 $(8) $(1) $18 |

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| - References
No definition available.
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| - Definition
Tabular disclosure of an entity's restructuring reserve that occurred during the period associated with the exit from or disposal of business activities or restructurings for each major type of cost. This element may also include a description of any reversal and other adjustment made during the period to the amount of an accrued liability for restructuring activities. This element may be used to encapsulate the roll forward presentations of an entity's restructuring reserve by type of cost and in total, and explanation of changes that occurred in the period.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(2)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747
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