| **Stockholders' Deficit Stockholder's Rights Plan (Policies)** | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Shareholder's Rights Plan [Abstract]**                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Stockholders' Equity Note Disclosure [Text Block]              | Stockholders' DeficitAccumulated Other Comprehensive Loss Changes in Accumulated other comprehensive loss, net of tax, included in the Consolidated Statements of Stockholders' Deficit, consisted of the following: (in millions)Unrealized Gain on Marketable Securities Foreign Currency Translation Adjustments Defined Benefit Plans TotalBalance as of January 31, 2016$1 $(320) $(2,282) $(2,601)Other comprehensive income (loss) before reclassifications— 50 (18) 32Amounts reclassified out of accumulated other comprehensive loss— — 33 33Net current-period other comprehensive income— 50 15 65Balance as of April 30, 2016$1 $(270) $(2,267) $(2,536)(in millions)Unrealized Gain on Marketable Securities Foreign Currency Translation Adjustments Defined Benefit Plans TotalBalance as of October 31, 2015$1 $(287) $(2,315) $(2,601)Other comprehensive income (loss) before reclassifications— 17 (18) (1)Amounts reclassified out of accumulated other comprehensive loss— — 66 66Net current-period other comprehensive income— 17 48 65Balance as of April 30, 2016$1 $(270) $(2,267) $(2,536)(in millions)Unrealized Gain on Marketable Securities Foreign Currency Translation Adjustments Defined Benefit Plans TotalBalance as of January 31, 2015$1 $(186) $(2,105) $(2,290)Other comprehensive loss before reclassifications— (27) — (27)Amounts reclassified out of accumulated other comprehensive loss— — 33 33Net current-period other comprehensive income (loss)— (27) 33 6Balance as of April 30, 2015$1 $(213) $(2,072) $(2,284)(in millions)Unrealized Gain on Marketable Securities Foreign Currency Translation Adjustments Defined Benefit Plans TotalBalance as of October 31, 2014$1 $(127) $(2,137) $(2,263)Other comprehensive loss before reclassifications— (86) — (86)Amounts reclassified out of accumulated other comprehensive loss— — 65 65Net current-period other comprehensive income (loss)— (86) 65 (21)Balance as of April 30, 2015$1 $(213) $(2,072) $(2,284)The following table displays the amounts reclassified from Accumulated other comprehensive loss and the affected line item in the Consolidated Statements of Operations:    Three Months Ended April 30, Six Months Ended April 30,  Location in Consolidated Statements of Operations 2016 2015 2016 2015Defined benefit plans          Amortization of prior service benefit Selling, general and administrative expenses $(1) $(1) $(1) $(2)Amortization of actuarial loss Selling, general and administrative expenses 34 34 67 68  Total before tax 33 33 66 66  Tax expense — — — (1)Total reclassifications for the period, net of tax $33 $33 $66 $65 |

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| - Definition
Shareholder's Rights Plan [Abstract]
+ References
No definition available.
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| - Definition
The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.
+ References
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