Income Taxes	6 Months Ended
Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	(11) INCOME TAXES The provision for income taxes for the three and six months ended September 30, 2018 is based on our projected annual effective tax rate for fiscal year 2019, adjusted for specific items that are required to be recognized in the period in which they are incurred. Our effective tax rate for the three and six months ended September 30, 2018 was 7.6 percent and 7.9 percent, respectively, as compared to 42.1 percent and 12.5 percent, respectively, for the same period in fiscal year 2018. The effective tax rate for the three and six months ended September 30, 2018 was impacted by the lower U.S. statutory tax rate as a result of the U.S. Tax Cuts and Jobs Act enacted on December 22, 2017 (the “U.S. Tax Act”) and earnings realized in countries that have lower statutory tax rates, partially offset by less excess tax benefits from stock-based compensation recognized in the current period as compared to the same period in fiscal year 2018. When compared to the statutory rate of 21.0 percent, the effective tax rate for the three and six months ended September 30, 2018 was lower due to earnings realized in countries that have lower statutory tax rates and the recognition of excess tax benefits from stock-based compensation. Excluding excess tax benefits, our effective tax rate would have been 9.8 percent and 10.6 percent, respectively, for the three and six months ended September 30, 2018. The U.S. Tax Act significantly revised the U.S. corporate income tax system by, among other things, lowering the U.S. corporate income tax rates to 21.0 percent, generally implementing a territorial tax system and imposing a one-time transition tax on the deemed repatriation of undistributed earnings of foreign subsidiaries (the “Transition Tax”). We recorded a provisional tax expense of $235 million related to the U.S. Tax Act for the fiscal year ended March 31, 2018, $192 million of which relates to the Transition Tax. During the three and six months ended September 30, 2018, we made no material adjustments to these provisional amounts. The final calculation of taxes attributable to the U.S. Tax Act may differ from our estimates, potentially materially, due to, among other things, changes in interpretations of the U.S. Tax Act, our further analysis of the U.S. Tax Act, or any updates or changes to estimates that we have utilized to calculate the transition impacts. Reasonable estimates of the impacts of the U.S. Tax Act are provided in accordance with SAB 118, the SEC guidance that allows for a measurement period of up to one year after the enactment date of the U.S. Tax Act to finalize the recording of the related tax impacts. We expect to complete the accounting under the U.S. Tax Act as soon as practicable, but in no event later than one year from the enactment date of the U.S. Tax Act. The U.S. Tax Act creates new U.S. taxes on foreign earnings. Our provision for income taxes for the three and six months ended September 30, 2018 provisionally does not reflect any deferred tax impacts of the U.S. taxes on foreign earnings. Because of the complexity of the rules regarding the new tax on foreign earnings, we are continuing to evaluate this accounting policy election. We file income tax returns and are subject to income tax examinations in various jurisdictions with respect to fiscal years after 2008. The timing and potential resolution of income tax examinations is highly uncertain. While we continue to measure our uncertain tax positions, the amounts ultimately paid, if any, upon resolution of the issues raised by the taxing authorities may differ materially from the amounts accrued. It is reasonably possible that a reduction of up to $16 million of unrecognized tax benefits may occur within the next 12 months, a portion of which would impact our effective tax rate. The actual amount could vary significantly depending on the ultimate timing and nature of any settlements and tax interpretations, including the Altera opinion.

(11) INCOME TAXES

The provision for income taxes for the three and six months ended September 30, 2018 is based on our projected annual effective tax rate for fiscal year 2019, adjusted for specific items that are required to be recognized in the period in which they are incurred.

Our effective tax rate for the three and six months ended September 30, 2018 was 7.6 percent and 7.9 percent, respectively, as compared to 42.1 percent and 12.5 percent, respectively, for the same period in fiscal year 2018. The effective tax rate for the three and six months ended September 30, 2018 was impacted by the lower U.S. statutory tax rate as a result of the U.S. Tax Cuts and Jobs Act enacted on December 22, 2017 (the “U.S. Tax Act”) and earnings realized in countries that have lower statutory tax rates, partially offset by less excess tax benefits from stock-based compensation recognized in the current period as compared to the same period in fiscal year 2018.

When compared to the statutory rate of 21.0 percent, the effective tax rate for the three and six months ended September 30, 2018 was lower due to earnings realized in countries that have lower statutory tax rates and the recognition of excess tax benefits from stock-based compensation. Excluding excess tax benefits, our effective tax rate would have been 9.8 percent and 10.6 percent, respectively, for the three and six months ended September 30, 2018.

The U.S. Tax Act significantly revised the U.S. corporate income tax system by, among other things, lowering the U.S. corporate income tax rates to 21.0 percent, generally implementing a territorial tax system and imposing a one-time transition tax on the deemed repatriation of undistributed earnings of foreign subsidiaries (the “Transition Tax”).

We recorded a provisional tax expense of $235 million related to the U.S. Tax Act for the fiscal year ended March 31, 2018, $192 million of which relates to the Transition Tax. During the three and six months ended September 30, 2018, we made no material adjustments to these provisional amounts. The final calculation of taxes attributable to the U.S. Tax Act may differ from our estimates, potentially materially, due to, among other things, changes in interpretations of the U.S. Tax Act, our further analysis of the U.S. Tax Act, or any updates or changes to estimates that we have utilized to calculate the transition impacts.

Reasonable estimates of the impacts of the U.S. Tax Act are provided in accordance with SAB 118, the SEC guidance that allows for a measurement period of up to one year after the enactment date of the U.S. Tax Act to finalize the recording of the related tax impacts. We expect to complete the accounting under the U.S. Tax Act as soon as practicable, but in no event later than one year from the enactment date of the U.S. Tax Act.

The U.S. Tax Act creates new U.S. taxes on foreign earnings. Our provision for income taxes for the three and six months ended September 30, 2018 provisionally does not reflect any deferred tax impacts of the U.S. taxes on foreign earnings. Because of the complexity of the rules regarding the new tax on foreign earnings, we are continuing to evaluate this accounting policy election.

We file income tax returns and are subject to income tax examinations in various jurisdictions with respect to fiscal years after 2008. The timing and potential resolution of income tax examinations is highly uncertain. While we continue to measure our uncertain tax positions, the amounts ultimately paid, if any, upon resolution of the issues raised by the taxing authorities may differ materially from the amounts accrued. It is reasonably possible that a reduction of up to $16 million of unrecognized tax benefits may occur within the next 12 months, a portion of which would impact our effective tax rate. The actual amount could vary significantly depending on the ultimate timing and nature of any settlements and tax interpretations, including the Altera opinion.