Income Taxes	6 Months Ended
Apr. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We compute, on a quarterly basis, an estimated annual effective tax rate considering ordinary income and related income tax expense. Tax jurisdictions with a projected or year to date loss for which a tax benefit cannot be realized are excluded. Ordinary income refers to income (loss) before income tax expense excluding significant unusual or infrequently occurring items. The tax effect of a significant unusual or infrequently occurring item is recorded in the interim period in which the item occurs. We included an income tax benefit of $38 million in the first quarter for the tax effect of a group annuity contract purchase for certain retired pension plan participants as a significant unusual or infrequently occurring item. Other items included in income tax expense in the periods in which they occur include the tax effects of cumulative changes in tax laws or rates, foreign exchange gains and losses, adjustments to uncertain tax positions, and adjustments to our valuation allowance due to changes in judgment regarding the ability to realize deferred tax assets in future years. On December 22, 2017, the Tax Act was signed into U.S. law. On December 22, 2017, Staff Accounting Bulletin No. 118 ("SAB 118") was issued to address the application of U.S. GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Tax Act. The Company’s financial statement effects were reported on a provisional basis for the year ended October 31, 2018. The remeasurement period for SAB 118 ended on December 22, 2018. The Tax Act reduced the statutory corporate income tax rate from 35% to 21%, effective January 1, 2018. This rate reduction required us to remeasure our deferred taxes as of the date the Tax Act was enacted. Our U.S. deferred tax assets, net of deferred tax liabilities, were remeasured and reduced by $983 million, entirely offset by a valuation allowance reduction. As a result, the remeasurement of our deferred tax assets, net of deferred tax liabilities, including the valuation allowance, did not impact our income tax expense or net income. The Tax Act also included a mandatory deemed repatriation of earnings of the Company’s foreign subsidiaries and resulted in a one-time transition tax for the year ended October 31, 2018. We included $147 million of foreign earnings in taxable income due to this deemed repatriation. The deferred tax impact had a valuation allowance offset, resulting in no impact on our income tax expense or net income. The income tax accounting for the effect of the rate change on deferred taxes and the mandatory deemed repatriation is complete. The Tax Act also included many other provisions, including changes to limits on the deductions for executive compensation and interest expense, a tax on global intangible low‐taxed income (“GILTI”), the base erosion anti‐abuse tax and a deduction for foreign derived intangible income. We have included the impact of these provisions in our interim period tax calculations, which first apply to our taxable year beginning November 1, 2018. Companies can either account for taxes on GILTI as incurred or recognize deferred taxes when basis differences exist that are expected to affect the amount of the GILTI inclusion upon reversal. The Company is electing to account for taxes on GILTI as incurred. We will continue to evaluate the Tax Act’s impact, which may change as a result of additional Treasury guidance, federal or state legislative actions, or changes in accounting standards or related interpretations. The Company’s analyses performed to date are sufficient to calculate a reasonable estimate of the impacts of the Tax Act. We have evaluated the need to maintain a valuation allowance for deferred tax assets based on our assessment of whether it is more likely than not that deferred tax benefits will be realized through the generation of future taxable income. Appropriate consideration is given to all available evidence, both positive and negative, in assessing the need for a valuation allowance. We continue to maintain a valuation allowance on the majority of our U.S. deferred tax assets as well as certain foreign deferred tax assets that we believe, on a more-likely-than-not basis, will not be realized based on current forecasted results. For all remaining deferred tax assets, while we believe that it is more likely than not that they will be realized, we believe that it is reasonably possible that additional deferred tax asset valuation allowances could be required in the next twelve months. We recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the consolidated financial statements from such a position are measured based on the largest benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. As of April 30, 2019, the amount of liability for uncertain tax positions was $21 million. The liability as of April 30, 2019 has a recorded offsetting tax benefit associated with various issues that total $9 million. If the unrecognized tax benefits are recognized, all would impact our effective tax rate, except for positions for which we maintain a full valuation allowance against certain deferred tax assets. In this case, the effect may be in the form of an increase in the deferred tax asset related to our net operating loss carryforward, which would be offset by a full valuation allowance. We recognize interest and penalties related to uncertain tax positions as part of Income tax expense. Total interest and penalties for the three and six months ended April 30, 2019 related to our uncertain tax positions resulted in an income tax expense of less than $1 million, for both periods. We have open tax years back to 2001 with various significant taxing jurisdictions, including the U.S., Canada, Mexico, and Brazil. In connection with the examination of tax returns, contingencies may arise that generally result from differing interpretations of applicable tax laws and regulations as they relate to the amount, timing, or inclusion of revenues or expenses in taxable income, or the sustainability of tax credits to reduce income taxes payable. We believe we have sufficient accruals for our contingent tax liabilities. Annual tax provisions include amounts considered sufficient to pay assessments that may result from examinations of prior year tax returns, although actual results may differ. While it is probable that the liability for unrecognized tax benefits may increase or decrease during the next twelve months, we do not expect any such change would have a material effect on our financial condition, results of operations, or cash flows.

Income Taxes

We compute, on a quarterly basis, an estimated annual effective tax rate considering ordinary income and related income tax expense. Tax jurisdictions with a projected or year to date loss for which a tax benefit cannot be realized are excluded. Ordinary income refers to income (loss) before income tax expense excluding significant unusual or infrequently occurring items. The tax effect of a significant unusual or infrequently occurring item is recorded in the interim period in which the item occurs. We included an income tax benefit of $38 million in the first quarter for the tax effect of a group annuity contract purchase for certain retired pension plan participants as a significant unusual or infrequently occurring item. Other items included in income tax expense in the periods in which they occur include the tax effects of cumulative changes in tax laws or rates, foreign exchange gains and losses, adjustments to uncertain tax positions, and adjustments to our valuation allowance due to changes in judgment regarding the ability to realize deferred tax assets in future years.

On December 22, 2017, the Tax Act was signed into U.S. law. On December 22, 2017, Staff Accounting Bulletin No. 118 ("SAB 118") was issued to address the application of U.S. GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Tax Act. The Company’s financial statement effects were reported on a provisional basis for the year ended October 31, 2018. The remeasurement period for SAB 118 ended on December 22, 2018. The Tax Act reduced the statutory corporate income tax rate from 35% to 21%, effective January 1, 2018. This rate reduction required us to remeasure our deferred taxes as of the date the Tax Act was enacted. Our U.S. deferred tax assets, net of deferred tax liabilities, were remeasured and reduced by $983 million, entirely offset by a valuation allowance reduction. As a result, the remeasurement of our deferred tax assets, net of deferred tax liabilities, including the valuation allowance, did not impact our income tax expense or net income. The Tax Act also included a mandatory deemed repatriation of earnings of the Company’s foreign subsidiaries and resulted in a one-time transition tax for the year ended October 31, 2018. We included $147 million of foreign earnings in taxable income due to this deemed repatriation. The deferred tax impact had a valuation allowance offset, resulting in no impact on our income tax expense or net income.

The income tax accounting for the effect of the rate change on deferred taxes and the mandatory deemed repatriation is complete.

The Tax Act also included many other provisions, including changes to limits on the deductions for executive compensation and interest expense, a tax on global intangible low‐taxed income (“GILTI”), the base erosion anti‐abuse tax and a deduction for foreign derived intangible income. We have included the impact of these provisions in our interim period tax calculations, which first apply to our taxable year beginning November 1, 2018. Companies can either account for taxes on GILTI as incurred or recognize deferred taxes when basis differences exist that are expected to affect the amount of the GILTI inclusion upon reversal. The Company is electing to account for taxes on GILTI as incurred.

We will continue to evaluate the Tax Act’s impact, which may change as a result of additional Treasury guidance, federal or state legislative actions, or changes in accounting standards or related interpretations. The Company’s analyses performed to date are sufficient to calculate a reasonable estimate of the impacts of the Tax Act.

We have evaluated the need to maintain a valuation allowance for deferred tax assets based on our assessment of whether it is more likely than not that deferred tax benefits will be realized through the generation of future taxable income. Appropriate consideration is given to all available evidence, both positive and negative, in assessing the need for a valuation allowance. We continue to maintain a valuation allowance on the majority of our U.S. deferred tax assets as well as certain foreign deferred tax assets that we believe, on a more-likely-than-not basis, will not be realized based on current forecasted results. For all remaining deferred tax assets, while we believe that it is more likely than not that they will be realized, we believe that it is reasonably possible that additional deferred tax asset valuation allowances could be required in the next twelve months.

We recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the consolidated financial statements from such a position are measured based on the largest benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. As of April 30, 2019, the amount of liability for uncertain tax positions was $21 million. The liability as of April 30, 2019 has a recorded offsetting tax benefit associated with various issues that total $9 million. If the unrecognized tax benefits are recognized, all would impact our effective tax rate, except for positions for which we maintain a full valuation allowance against certain deferred tax assets. In this case, the effect may be in the form of an increase in the deferred tax asset related to our net operating loss carryforward, which would be offset by a full valuation allowance.

We recognize interest and penalties related to uncertain tax positions as part of Income tax expense. Total interest and penalties for the three and six months ended April 30, 2019 related to our uncertain tax positions resulted in an income tax expense of less than $1 million, for both periods.

We have open tax years back to 2001 with various significant taxing jurisdictions, including the U.S., Canada, Mexico, and Brazil. In connection with the examination of tax returns, contingencies may arise that generally result from differing interpretations of applicable tax laws and regulations as they relate to the amount, timing, or inclusion of revenues or expenses in taxable income, or the sustainability of tax credits to reduce income taxes payable. We believe we have sufficient accruals for our contingent tax liabilities. Annual tax provisions include amounts considered sufficient to pay assessments that may result from examinations of prior year tax returns, although actual results may differ. While it is probable that the liability for unrecognized tax benefits may increase or decrease during the next twelve months, we do not expect any such change would have a material effect on our financial condition, results of operations, or cash flows.