Estimated Amortization Expense (Detail) $ in Thousands	Apr. 30, 2017 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Estimated annual amortization expense, For the fiscal year ending July 31, 2017	$ 63,925
Estimated annual amortization expense, For the fiscal year ending July 31, 2018	54,463
Estimated annual amortization expense, For the fiscal year ending July 31, 2019	50,367
Estimated annual amortization expense, For the fiscal year ending July 31, 2020	46,480
Estimated annual amortization expense, For the fiscal year ending July 31, 2021	43,131
Estimated annual amortization expense, For the fiscal year ending July 31, 2022 and thereafter	249,025
Estimated annual amortization expense, Total	$ 507,391