Income Taxes	9 Months Ended
Income Taxes	Oct. 31, 2020
Federal, State And Foreign
Income Tax Contingency [Line Items]
Income Taxes	Income Taxes On March 27, 2020, the U.S. federal government passed the Coronavirus Aid, Relief, and Economic Security Act ("CARES Act"). The CARES Act contains many tax provisions including, but not limited to, accelerated alternative minimum tax ("AMT") refunds, payroll tax payment deferrals, employee retention credits, enhanced net operating loss ("NOL") carryback rules and an increase to the interest deduction limitation. The Company has considered the income tax provisions of the CARES Act in the tax benefit calculation for the nine months ended October 31, 2020. The Company continues to monitor and analyze the CARES Act along with global legislation issued in response to the COVID-19 pandemic. The net tax expense of $1 million for the three months ended October 31, 2020, consisted of $1 million of expense related to the deferred tax asset change arising from the tax amortization of indefinite-lived intangible assets. The net tax benefit of $66 million for the nine months ended October 31, 2020, consisted of federal, state and foreign tax benefit of $1 million, $3 million of expense related to the deferred tax asset change arising from the tax amortization of indefinite-lived intangible assets, net tax benefit of $3 million resulting from statutory audit settlements and a $65 million benefit from the release of valuation allowance, primarily due to the generation of post-tax reform NOLs that do not expire. As of October 31, 2020, we have approximately $2.7 billion of NOLs available for U.S. federal income tax purposes, which largely expire in 2032 through 2034, though about $615 million of the NOLs do not expire; $473 million of federal unused interest deductions that do not expire; and $76 million of tax credit carryforwards that expire at various dates through 2039. Additionally, we have state NOLs that are subject to various limitations and expiration dates beginning in 2020 through 2041 and are offset fully by valuation allowances. A valuation allowance of $866 million fully offsets the federal deferred tax assets resulting from the NOLs, unused interest deductions and tax credit carryforwards that expire at various dates through 2039. A valuation allowance of $274 million fully offsets the deferred tax assets resulting from the state NOL carryforwards that expire at various dates through 2041. In assessing the need for the valuation allowance, we considered both positive and negative evidence related to the likelihood of realization of the deferred tax assets. As a result of our periodic assessment, our estimate of the realization of deferred tax assets is solely based on the future reversals of existing taxable temporary differences and tax credit carryforwards. Accordingly, in the three months ended October 31, 2020, the valuation allowance net increase of $86 million consisted of net deferred tax assets created in the quarter primarily due to the increase in NOL carryforwards. Our ability to use our NOLs may become subject to limitation or may be reduced or eliminated in connection with the Chapter 11 Cases.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.