Income Taxes	3 Months Ended
Jul. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective income tax rate for the three-month periods ended July 31, 2018 and 2017 was 23.8% and 29.0%, respectively. The decrease in the effective tax rate for the first quarter of fiscal 2019, as compared to the first quarter of fiscal 2018, was primarily due to a benefit from the reduction in the federal corporate tax rate enacted in connection with the Tax Cuts and Jobs Act of 2017 (H.R. 1) (the “Tax Act”) from 35% to 21%. This was partially offset by the decrease of the benefit from stock-based compensation transactions and the repeal of the domestic production activities deduction by the Tax Act. During the first quarters of fiscal 2019 and 2018, the Company recognized an excess tax benefit related to stock-based compensation transactions of $0.7 million and $2.2 million, respectively. Comprehensive tax legislation enacted through the Tax Act on December 22, 2017 significantly modified U.S. corporate income tax law. In addition to its corporate income tax rate reduction, several other provisions of the Tax Act impacted the Company's financial statements and related disclosures for the year ended April 30, 2018 or will have an impact on taxes in future years. The Company recognized the income tax effects of the Tax Act in accordance with Staff Accounting Bulletin No. 118 (“SAB 118”) which provides SEC guidance on the application of ASC 740, Income Taxes, in the reporting period in which the Tax Act was signed into law. Accordingly, the Company’s financial statements as of April 30, 2018 reflected provisional amounts for those impacts for which the accounting under ASC 740 was incomplete, but a reasonable estimate could be determined. For items under the Tax Act for which no reasonable estimate could be determined at the time, the Company continued to apply the tax law in effect prior to the enactment of the Tax Act. As of July 31, 2018, the Company is still in the process of completing the accounting for the impact of the Tax Act. The Company recorded a provisional expense of $1.0 million related to the re-valuation of U.S. deferred taxes as of April 30, 2018. During the three months ended July 31, 2018, there were no changes to the provisional estimates previously recorded and no additional measurement period adjustments were recorded. The Company may further adjust this amount in future periods if our interpretation of the Tax Act changes or as additional guidance from the U.S. Treasury becomes available. As of April 30, 2018, the Company recorded a reduction in deferred tax assets related to executive compensation of $0.1 million. Since guidance on this provision of the Tax Act was issued by the Internal Revenue Service after July 31, 2018, the Company has not recorded a change to the estimate of the impact during the three months ended July 31, 2018. This estimate is provisional and the Company may further adjust these amounts in future periods if its interpretation of the Tax Act changes or as further additional guidance from the U.S. Treasury becomes available.

Income Taxes

The effective income tax rate for the three-month periods ended July 31, 2018 and 2017 was 23.8% and 29.0%, respectively. The decrease in the effective tax rate for the first quarter of fiscal 2019, as compared to the first quarter of fiscal 2018, was primarily due to a benefit from the reduction in the federal corporate tax rate enacted in connection with the Tax Cuts and Jobs Act of 2017 (H.R. 1) (the “Tax Act”) from 35% to 21%. This was partially offset by the decrease of the benefit from stock-based compensation transactions and the repeal of the domestic production activities deduction by the Tax Act. During the first quarters of fiscal 2019 and 2018, the Company recognized an excess tax benefit related to stock-based compensation transactions of $0.7 million and $2.2 million, respectively.

Comprehensive tax legislation enacted through the Tax Act on December 22, 2017 significantly modified U.S. corporate income tax law. In addition to its corporate income tax rate reduction, several other provisions of the Tax Act impacted the Company's financial statements and related disclosures for the year ended April 30, 2018 or will have an impact on taxes in future years.

The Company recognized the income tax effects of the Tax Act in accordance with Staff Accounting Bulletin No. 118 (“SAB 118”) which provides SEC guidance on the application of ASC 740, Income Taxes, in the reporting period in which the Tax Act was signed into law. Accordingly, the Company’s financial statements as of April 30, 2018 reflected provisional amounts for those impacts for which the accounting under ASC 740 was incomplete, but a reasonable estimate could be determined. For items under the Tax Act for which no reasonable estimate could be determined at the time, the Company continued to apply the tax law in effect prior to the enactment of the Tax Act. As of July 31, 2018, the Company is still in the process of completing the accounting for the impact of the Tax Act.

The Company recorded a provisional expense of $1.0 million related to the re-valuation of U.S. deferred taxes as of April 30, 2018. During the three months ended July 31, 2018, there were no changes to the provisional estimates previously recorded and no additional measurement period adjustments were recorded. The Company may further adjust this amount in future periods if our interpretation of the Tax Act changes or as additional guidance from the U.S. Treasury becomes available.

As of April 30, 2018, the Company recorded a reduction in deferred tax assets related to executive compensation of $0.1 million. Since guidance on this provision of the Tax Act was issued by the Internal Revenue Service after July 31, 2018, the Company has not recorded a change to the estimate of the impact during the three months ended July 31, 2018. This estimate is provisional and the Company may further adjust these amounts in future periods if its interpretation of the Tax Act changes or as further additional guidance from the U.S. Treasury becomes available.