Stockholders' Equity (Details) - USD ($)	9 Months Ended
	Apr. 30, 2016	Apr. 30, 2015	Jun. 08, 2016	Mar. 10, 2016	Dec. 09, 2015	Sep. 28, 2015
Treasury Stock Transactions, Excluding Value of Shares Reissued [Abstract]
Stock repurchase program, remaining authorized repurchase amount	$ 8,664,000
Maximum amount authorized by the Board of Directors for repurchases of the Company's common stock	$ 100,000,000
Repurchases of common stock (in shares)	0	175,735
Average repurchase price (in dollars per share)		$ 28.39
Repurchases of common stock		$ 4,989,000
Dividends [Abstract]
Targeted annual dividend per share (in dollars per share)	$ 1.20	$ 1.20
Quarterly dividend payment amount per share (in dollars per share)				$ 0.30	$ 0.30	$ 0.30
Subsequent Event [Member]
Treasury Stock Transactions, Excluding Value of Shares Reissued [Abstract]
Stock repurchase program, remaining authorized repurchase amount			$ 8,664,000
Dividends [Abstract]
Quarterly dividend payment amount per share (in dollars per share)			$ 0.30