Schedule Of Estimated Annual Amortization Expense (Detail) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013
Expected Amortization Expense [Line Items]
Estimated annual amortization expense, For the fiscal year ending July 31, 2013	$ 11,145
Estimated annual amortization expense, For the fiscal year ending July 31, 2014	10,919
Estimated annual amortization expense, For the fiscal year ending July 31, 2015	10,560
Estimated annual amortization expense, For the fiscal year ending July 31, 2016	9,504
Estimated annual amortization expense, For the fiscal year ending July 31, 2017	9,117
Estimated annual amortization expense, For the fiscal year ending July 31, 2018 and thereafter	$ 65,982