Changes in Accumulated Other Comprehensive Income (Details) - USD ($)	3 Months Ended		9 Months Ended
	Nov. 03, 2018	Oct. 28, 2017	Nov. 03, 2018	Oct. 28, 2017
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance Accumulated other comprehensive income, net of tax			$ (321,000)
Unrealized gain on available-for-sale securities, net of deferred income taxes	$ (373,000)	$ (170,000)	(451,000)	$ 455,000
Ending Balance Accumulated other comprehensive income, net of tax	(772,000)		(772,000)
ChangeInUnrealizedGainsOnAvailableForSaleSecuritiesMember [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance Accumulated other comprehensive income, net of tax	(399,000)	411,000	(321,000)	(214,000)
Other Comprehensive Income Loss Before Reclassifications Net Of Tax	(373,000)	(144,000)	(504,000)	478,000
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax	0	(26,000)	53,000	(23,000)
Unrealized gain on available-for-sale securities, net of deferred income taxes	(373,000)	(170,000)	(451,000)	455,000
Ending Balance Accumulated other comprehensive income, net of tax	$ (772,000)	$ 241,000	$ (772,000)	$ 241,000