Income Taxes	6 Months Ended
Oct. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Our consolidated interim effective tax rate is based upon our expected annual operating income, statutory tax rates, and income tax laws in the various jurisdictions in which we operate. Significant or unusual items, including adjustments to accruals for tax uncertainties, are recognized in the fiscal quarter in which the related event or a change in judgment occurs. The effective tax rate of 18.6% for the six months ended October 31, 2018, is lower than the expected tax rate of 21.4% on ordinary income for the full fiscal year, primarily due to (a) the impact of discrete items, including true-ups to prior year tax returns, (b) the impact of the current year net adjustment to the provisional repatriation U.S. tax charge that was made during fiscal 2018 (discussed below), and (c) the excess tax benefits related to stock-based compensation. Our expected tax rate includes current fiscal year additions for existing tax contingency items. On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act (Tax Act). The Tax Act significantly revised the future ongoing U.S. corporate income tax by, among other things, lowering U.S. corporate income tax rates and implementing a territorial tax system. As we have an April 30 fiscal year-end, the lower corporate income tax rate was phased in, resulting in a U.S. statutory federal rate of 30.4% for our fiscal year ended April 30, 2018, and 21% for our current and subsequent fiscal years. For the six months ended October 31, 2018, the impact of reducing the U.S. statutory federal rate from 35% (the pre-Tax Act rate) to 21% resulted in a tax benefit of approximately $60 million. There are also certain transitional impacts of the Tax Act. As part of the transition to the new territorial tax system, the Tax Act imposed a one-time repatriation tax on deemed repatriation of historical earnings of foreign subsidiaries. In addition, the reduction of the U.S. corporate tax rate caused us to adjust our U.S. deferred tax assets and liabilities to the lower federal base rate of 21%. These transitional impacts resulted in a provisional net charge of $43 million for the year ended April 30, 2018, comprised of a provisional repatriation U.S. tax charge of $91 million and a provisional net deferred tax benefit of $48 million. In the six months ended October 31, 2018, we recorded a benefit of $4 million as an adjustment to the provisional repatriation tax. Historically, we have asserted that the undistributed earnings of our foreign subsidiaries are reinvested indefinitely outside the United States. Therefore, no income taxes have been provided for any outside basis differences inherent in these subsidiaries other than those subject to the one-time repatriation tax. As of October 31, 2018, we changed our indefinite reinvestment assertion with respect to current year earnings and prior year undistributed earnings for one of those foreign subsidiaries (but not for its other outside basis differences). We intend to repatriate approximately $120 million of cash to the United States from this subsidiary during the fiscal quarter ending January 31, 2019. No incremental taxes are due on this distribution of cash beyond the repatriation tax recorded in fiscal year 2018. We have not changed the indefinite reinvestment assertion for undistributed earnings or other outside basis differences for any of the other foreign subsidiaries. We will continue to evaluate our future cash deployment and may change our indefinite reinvestment assertion in future periods. The Tax Act also established new tax laws that impact our financial statements beginning in the current fiscal year. These new laws include, but are not limited to (a) Global Intangible Low-Tax Income (GILTI), a new provision for tax on low-tax foreign earnings; (b) Base Erosion Anti-abuse Tax (BEAT), a new minimum tax; (c) Foreign-Derived Intangible Income (FDII), a new provision for deductions related to foreign-derived intangibles; (d) repeal of the domestic production activity deduction; and (e) limitations on certain executive compensation. For the six months ended October 31, 2018, the net impact of these provisions was approximately $7 million of additional tax. As noted, certain income earned by foreign subsidiaries must be included in U.S. taxable income under the GILTI provisions. The FASB allows an accounting policy election of either recognizing deferred taxes for temporary differences expected to reverse as GILTI in future years or recognizing such taxes as a current period expense when incurred. We have elected to recognize these taxes as a current period expense when incurred. The changes included in the Tax Act are broad and complex. The final transition impacts of the Tax Act may differ from the current estimates, due to, among other things, changes in interpretations of the Tax Act, any legislative action to address questions that arise because of the Tax Act, any changes in accounting standards for income taxes or related interpretations in response to the Tax Act, or any updates or changes to estimates we have used to calculate the transition impacts, including impacts from changes to current year earnings estimates and foreign currency exchange rates. The SEC has issued rules that allow for a measurement period of up to one year after the enactment date of the Tax Act to finalize the recording of the related tax impacts. As of October 31, 2018, the amounts recorded for the Tax Act remain provisional for the one-time repatriation tax and the adjustment to our U.S. deferred tax assets and liabilities. We will finalize and record any additional adjustments within the allowed measurement period.

Income Taxes

Our consolidated interim effective tax rate is based upon our expected annual operating income, statutory tax rates, and income tax laws in the various jurisdictions in which we operate. Significant or unusual items, including adjustments to accruals for tax uncertainties, are recognized in the fiscal quarter in which the related event or a change in judgment occurs. The effective tax rate of 18.6% for the six months ended October 31, 2018, is lower than the expected tax rate of 21.4% on ordinary income for the full fiscal year, primarily due to (a) the impact of discrete items, including true-ups to prior year tax returns, (b) the impact of the current year net adjustment to the provisional repatriation U.S. tax charge that was made during fiscal 2018 (discussed below), and (c) the excess tax benefits related to stock-based compensation. Our expected tax rate includes current fiscal year additions for existing tax contingency items.

On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act (Tax Act). The Tax Act significantly revised the future ongoing U.S. corporate income tax by, among other things, lowering U.S. corporate income tax rates and implementing a territorial tax system. As we have an April 30 fiscal year-end, the lower corporate income tax rate was phased in, resulting in a U.S. statutory federal rate of 30.4% for our fiscal year ended April 30, 2018, and 21% for our current and subsequent fiscal years. For the six months ended October 31, 2018, the impact of reducing the U.S. statutory federal rate from 35% (the pre-Tax Act rate) to 21% resulted in a tax benefit of approximately $60 million.

There are also certain transitional impacts of the Tax Act. As part of the transition to the new territorial tax system, the Tax Act imposed a one-time repatriation tax on deemed repatriation of historical earnings of foreign subsidiaries. In addition, the reduction of the U.S. corporate tax rate caused us to adjust our U.S. deferred tax assets and liabilities to the lower federal base rate of 21%. These transitional impacts resulted in a provisional net charge of $43 million for the year ended April 30, 2018, comprised of a provisional repatriation U.S. tax charge of $91 million and a provisional net deferred tax benefit of $48 million. In the six months ended October 31, 2018, we recorded a benefit of $4 million as an adjustment to the provisional repatriation tax.

Historically, we have asserted that the undistributed earnings of our foreign subsidiaries are reinvested indefinitely outside the United States. Therefore, no income taxes have been provided for any outside basis differences inherent in these subsidiaries other than those subject to the one-time repatriation tax. As of October 31, 2018, we changed our indefinite reinvestment assertion with respect to current year earnings and prior year undistributed earnings for one of those foreign subsidiaries (but not for its other outside basis differences). We intend to repatriate approximately $120 million of cash to the United States from this subsidiary during the fiscal quarter ending January 31, 2019. No incremental taxes are due on this distribution of cash beyond the repatriation tax recorded in fiscal year 2018. We have not changed the indefinite reinvestment assertion for undistributed earnings or other outside basis differences for any of the other foreign subsidiaries. We will continue to evaluate our future cash deployment and may change our indefinite reinvestment assertion in future periods.

The Tax Act also established new tax laws that impact our financial statements beginning in the current fiscal year. These new laws include, but are not limited to (a) Global Intangible Low-Tax Income (GILTI), a new provision for tax on low-tax foreign earnings; (b) Base Erosion Anti-abuse Tax (BEAT), a new minimum tax; (c) Foreign-Derived Intangible Income (FDII), a new provision for deductions related to foreign-derived intangibles; (d) repeal of the domestic production activity deduction; and (e) limitations on certain executive compensation. For the six months ended October 31, 2018, the net impact of these provisions was approximately $7 million of additional tax.

As noted, certain income earned by foreign subsidiaries must be included in U.S. taxable income under the GILTI provisions. The FASB allows an accounting policy election of either recognizing deferred taxes for temporary differences expected to reverse as GILTI in future years or recognizing such taxes as a current period expense when incurred. We have elected to recognize these taxes as a current period expense when incurred.

The changes included in the Tax Act are broad and complex. The final transition impacts of the Tax Act may differ from the current estimates, due to, among other things, changes in interpretations of the Tax Act, any legislative action to address questions that arise because of the Tax Act, any changes in accounting standards for income taxes or related interpretations in response to the Tax Act, or any updates or changes to estimates we have used to calculate the transition impacts, including impacts from changes to current year earnings estimates and foreign currency exchange rates. The SEC has issued rules that allow for a measurement period of up to one year after the enactment date of the Tax Act to finalize the recording of the related tax impacts. As of October 31, 2018, the amounts recorded for the Tax Act remain provisional for the one-time repatriation tax and the adjustment to our U.S. deferred tax assets and liabilities. We will finalize and record any additional adjustments within the allowed measurement period.