| **Postretirement Benefits**                           | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 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| **Compensation and Retirement Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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| Postretirement Benefits                               | Postretirement BenefitsDefined Benefit PlansWe provide postretirement benefits to a substantial portion of our employees and retirees. Costs associated with postretirement benefits include pension and postretirement health care expenses for employees, retirees, and surviving spouses and dependents. Generally, the pension plans are non-contributory. Our policy is to fund the pension plans in accordance with applicable U.S. and Canadian government regulations and to make additional contributions from time to time. For the three and six months ended April 30, 2014, we contributed $36 million and $65 million, respectively, and for the three and six months ended April 30, 2013 we contributed $30 million and $57 million, respectively, to our pension plans to meet regulatory funding requirements. We currently anticipate additional contributions of $133 million to our pension plans during the remainder of 2014. We primarily fund other post-employment benefit ("OPEB") obligations, such as retiree medical, in accordance with a 1993 Settlement Agreement (the "1993 Settlement Agreement"), which requires us to fund a portion of the plans' annual service cost to a retiree benefit trust (the "Base Trust"). The 1993 Settlement Agreement resolved a class action lawsuit originally filed in 1992 regarding the restructuring of the Company's then applicable retiree health care and life insurance benefits. Contributions for the six months ended April 30, 2014 and 2013, as well as anticipated contributions for the remainder of 2014, are not material.Components of Net Periodic Benefit Expense (Income)Net postretirement benefits expense included in our Consolidated Statements of Operations is comprised of the following: Three Months Ended April 30, Six Months Ended April 30, Pension Benefits Health and LifeInsurance Benefits Pension Benefits Health and LifeInsurance Benefits(in millions)2014 2013 2014 2013 2014 2013 2014 2013Service cost for benefits earned during the period$2 $5 $1 $2 $6 $10 $2 $4Interest on obligation40 36 17 16 79 72 34 31Amortization of cumulative loss23 32 4 8 47 64 8 15Amortization of prior service benefit— — (1) (1) — — (2) (2)Premiums on pension insurance— 1 — — — 1 — —Expected return on assets(48) (47) (8) (9) (96) (94) (16) (17)Net postretirement benefits expense$17 $27 $13 $16 $36 $53 $26 $31Defined Contribution Plans and Other Contractual ArrangementsOur defined contribution plans cover a substantial portion of domestic salaried employees and certain domestic represented employees. The defined contribution plans contain a 401(k) feature and provide most participants with a matching contribution from the Company. Effective February 1, 2013, the Company changed the timing for depositing the matching contributions to the end of the calendar year. Many participants covered by the plans receive annual Company contributions to their retirement accounts based on an age-weighted percentage of the participant's eligible compensation for the calendar year. Defined contribution expense pursuant to these plans was $7 million and $15 million in the three and six months ended April 30, 2014, respectively, and $8 million and $15 million for the three and six months ended April 30, 2013, respectively. In accordance with the 1993 Settlement Agreement, an independent Retiree Supplemental Benefit Trust (the "Supplemental Trust") was established. The Supplemental Trust, and the benefits it provides to certain retirees pursuant to a certain Retiree Supplemental Benefit Program under the 1993 Settlement Agreement ("Supplemental Benefit Program"), is not part of the Company's consolidated financial statements. The assets of the Supplemental Trust arise from three sources: (i) the Company's 1993 contribution to the Supplemental Trust of 25.5 million shares of our Class B common stock, which were subsequently sold by the Supplemental Trust prior to 2000, (ii) contingent profit-sharing contributions made by the Company pursuant to a certain Supplemental Benefit Trust Profit Sharing Plan ("Supplemental Benefit Profit Sharing Plan"), and (iii) net investment gains on the Supplemental Trust's assets, if any. The Company's contingent profit sharing obligations under the Supplemental Benefits Profit Sharing Plan will continue until certain funding targets defined by the 1993 Settlement Agreement are met ("Profit Sharing Cessation"). Upon Profit Sharing Cessation, the Company would assume responsibility for (i) establishing the investment policy for the Supplemental Trust, (ii) approving or disapproving of certain additional supplemental benefits to the extent such benefits would result in higher expenditures than those contemplated upon the Profit Sharing Cessation, and (iii) making additional contributions to the Supplemental Trust as necessary to make up for investment and/or actuarial losses.We have recorded no profit sharing accruals based on the operating performance of the entities that are included in the determination of qualifying profits. For more information, see Note 12, Commitments and Contingencies, for a discussion of pending litigation regarding the Supplemental Benefit Profit Sharing Plan. |

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| - Definition
The entire disclosure for pension and other postretirement benefits.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -URI http://asc.fasb.org/topic&trid=2235017
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