Earnings Per Common Share - Weighted Average Shares (Details) - shares	12 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Reconciliation of weighted average number of shares and common stock equivalents attributable to common stock, to the entity's total weighted average number of shares and common stock equivalents, including participating securities
Denominator for diluted earnings per share - weighted average number of shares and common stock equivalents attributable to common stock (in shares)	41,757,116	41,635,078	41,542,765
Participating securities (in shares)	38,905	148,700	254,727
Total weighted average number of shares and common stock equivalents attributable to both common stock and participating securities (in shares)	41,796,021	41,783,778	41,797,492