Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Nov. 07, 2016	Oct. 28, 2016	Oct. 30, 2015
Shareholders' Equity [Abstract]
Number of shares issued from vesting of share-based compensation awards and stock option exercises (in shares)		76,233
Tax withholding payment net of cash received from issuance of share based compensation awards		$ 6,138	$ 5,243
Share-based compensation expense		1,425	1,952
Excess tax benefit realized upon exercise of share-based compensation awards		$ 1,062	$ 1,920
Dividends Payable [Line Items]
Cash dividends paid (in dollars per share)		$ 1.15	$ 4.10
Cash dividends declared (in dollars per share)		1.15	$ 1.10
Regular Quarterly Dividend Declared in Q4 [Member]
Dividends Payable [Line Items]
Cash dividends paid (in dollars per share)		1.15
Regular Quarterly Dividend Declared in Q1 [Member]
Dividends Payable [Line Items]
Cash dividends declared (in dollars per share)		$ 1.15
Dividend record date		Oct. 14, 2016
Regular Quarterly Dividend Declared in Q1 [Member] | Subsequent Event [Member]
Dividends Payable [Line Items]
Cash dividends paid (in dollars per share)	$ 1.15
Dividend payment date	Nov. 07, 2016