Earnings Per Common Share (Detail) - shares	3 Months Ended
	Oct. 31, 2015	Oct. 31, 2014
Earnings Per Share Disclosure [Line Items]
Weighted average common shares outstanding for basic earnings per share	52,409,945	53,336,592
Stock options, unvested restricted stock and restricted stock units	135,615	96,855
Weighted average common shares outstanding for diluted earnings per share	52,545,560	53,433,447