Income Taxes	6 Months Ended
Jan. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	14. Income Taxes Income tax expense for the interim periods was computed using an estimated annual effective income tax rate applied to year-to-date income before income tax expense. In determining the estimated annual effective income tax rate, the Company analyzes various factors, including forecasts of projected annual earnings and the ability to use tax credits and net operating loss carry forwards. The overall effective income tax rate for the three and six months ended January 31, 2018 was (47.7)% and (21.7)%, respectively. For the three and six months ended January 31, 2017, the overall effective income tax rate was 24.4% and 29.4%, respectively. The decrease in the effective tax rate from the prior fiscal year was due to one-time tax benefits reflecting the impact of the re‑measurement of net deferred tax liabilities resulting from the Tax Cuts and Jobs Act of 2017 described below, and stock-based compensation tax benefits realized as a result of the adoption of ASU 2016-09 in the second quarter of fiscal year 2017. On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act of 2017 (the “Tax Act”). The Tax Act significantly revises the future ongoing U.S. corporate income tax by, among other things, lowering the U.S. corporate income tax rate from 35% to 21%, changing how foreign earnings are subject to U.S. tax by implementing a territorial tax system, and eliminating certain deductions, including the domestic manufacturing deduction. The Tax Act also enhances and extends through 2026 the option to claim accelerated depreciation deductions on qualified property. As the Company has a July 31 fiscal year-end, the lower corporate income tax rate will be phased in, resulting in an estimated U.S. statutory federal rate of approximately 27% for our fiscal year ending July 31, 2018, and 21% for subsequent fiscal years. Under GAAP, the Company is required to recognize the effects of changes in tax laws and tax rates on deferred tax assets and liabilities in the period in which the new legislation is enacted. For the fiscal quarter ended January 31, 2018, the Company recorded a net tax benefit of approximately $11.0 million from the new legislation. The tax benefit mainly reflects the impact of the re-measurement of net deferred tax liabilities resulting from the permanent reduction in the U.S. statutory corporate tax rate from 35% to 21%. There are also certain transitional impacts of the Tax Act. As part of the transition to the new territorial tax system, the Tax Act imposes a one-time repatriation tax on deemed repatriation of historical earnings of foreign subsidiaries. However, the Company does not believe the transitional tax is material. The changes included in the Tax Act are broad and complex and the Company does not have all the necessary information to analyze all income tax effects of the Tax Act. The above income tax benefit amount is a provisional amount based on a reasonable estimate of the impact of the reduction in corporate tax rate on our current and deferred tax liabilities. Changes in the estimate of our deferred tax asset and liability activity during fiscal year 2018 could impact our remeasurement of net deferred tax liabilities. In addition, there is uncertainty about the interpretation of the Tax Act and the Internal Revenue Service guidance on the Tax Act. The Company’s estimation of the one-time repatriation tax may differ from the provision amount as a result of the uncertainty from the interpretation of the Tax Act and changes in the estimate of historical earnings of foreign corporations. The Company will continue to evaluate the Tax Act and adjust the provisional amounts as additional information becomes available. The ultimate impact of the Tax Act may differ from the provisional amounts due to changes in the Company’s interpretations and assumptions, as well as additional guidance on the interpretation of the Tax Act.

14. Income Taxes

Income tax expense for the interim periods was computed using an estimated annual effective income tax rate applied to year-to-date income before income tax expense. In determining the estimated annual effective income tax rate, the Company analyzes various factors, including forecasts of projected annual earnings and the ability to use tax credits and net operating loss carry forwards. The overall effective income tax rate for the three and six months ended January 31, 2018 was (47.7)% and (21.7)%, respectively. For the three and six months ended January 31, 2017, the overall effective income tax rate was 24.4% and 29.4%, respectively. The decrease in the effective tax rate from the prior fiscal year was due to one-time tax benefits reflecting the impact of the re‑measurement of net deferred tax liabilities resulting from the Tax Cuts and Jobs Act of 2017 described below, and stock-based compensation tax benefits realized as a result of the adoption of ASU 2016-09 in the second quarter of fiscal year 2017.

On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act of 2017 (the “Tax Act”). The Tax Act significantly revises the future ongoing U.S. corporate income tax by, among other things, lowering the U.S. corporate income tax rate from 35% to 21%, changing how foreign earnings are subject to U.S. tax by implementing a territorial tax system, and eliminating certain deductions, including the domestic manufacturing deduction. The Tax Act also enhances and extends through 2026 the option to claim accelerated depreciation deductions on qualified property. As the Company has a July 31 fiscal year-end, the lower corporate income tax rate will be phased in, resulting in an estimated U.S. statutory federal rate of approximately 27% for our fiscal year ending July 31, 2018, and 21% for subsequent fiscal years. Under GAAP, the Company is required to recognize the effects of changes in tax laws and tax rates on deferred tax assets and liabilities in the period in which the new legislation is enacted.

For the fiscal quarter ended January 31, 2018, the Company recorded a net tax benefit of approximately $11.0 million from the new legislation. The tax benefit mainly reflects the impact of the re-measurement of net deferred tax liabilities resulting from the permanent reduction in the U.S. statutory corporate tax rate from 35% to 21%.

There are also certain transitional impacts of the Tax Act. As part of the transition to the new territorial tax system, the Tax Act imposes a one-time repatriation tax on deemed repatriation of historical earnings of foreign subsidiaries. However, the Company does not believe the transitional tax is material.

The changes included in the Tax Act are broad and complex and the Company does not have all the necessary information to analyze all income tax effects of the Tax Act. The above income tax benefit amount is a provisional amount based on a reasonable estimate of the impact of the reduction in corporate tax rate on our current and deferred tax liabilities. Changes in the estimate of our deferred tax asset and liability activity during fiscal year 2018 could impact our remeasurement of net deferred tax liabilities. In addition, there is uncertainty about the interpretation of the Tax Act and the Internal Revenue Service guidance on the Tax Act. The Company’s estimation of the one-time repatriation tax may differ from the provision amount as a result of the uncertainty from the interpretation of the Tax Act and changes in the estimate of historical earnings of foreign corporations. The Company will continue to evaluate the Tax Act and adjust the provisional amounts as additional information becomes available. The ultimate impact of the Tax Act may differ from the provisional amounts due to changes in the Company’s interpretations and assumptions, as well as additional guidance on the interpretation of the Tax Act.