Shareholders' Equity (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Aug. 31, 2016	Aug. 31, 2015	Jan. 28, 2017	Jan. 30, 2016	Jan. 28, 2017	Jan. 30, 2016	Jul. 31, 2016	Aug. 31, 2010
Cash Dividends [Abstract]
Cash dividends declared			$ 859	$ 1,034	$ 859	$ 1,034
Dividends paid	$ 900	$ 1,000
Accumulated Other Comprehensive Loss [Abstract]
Unrealized net foreign currency translation losses			(2,115)		(2,115)		$ (2,176)
Unrealized net investment gains on available for sale investments			2		2		33
Total accumulated other comprehensive loss			$ (2,113)		$ (2,113)		$ (2,143)
Class A [Member]
Class A and Class B common stock [Abstract]
Percentage equity holders entitled to elect Board of Directors					25.00%
Minimum percentage of the number of outstanding Class A shares to combined classes of shares					10.00%
Voting power of Class A common share holders to the Class B common share holders					0.1
Number of Class B shares to be converted into Class A shares (in shares)					1
Stock Repurchase [Abstract]
Number of shares authorized to be repurchased (in shares)								200,000
Number of shares repurchased during the period (in shares)					122,918
Remaining number of shares authorized to be repurchased (in shares)			77,082		77,082
Number of share acquired (in shares)					0	0