Investments (Summary Of Investments) (Details) (USD $) In Thousands	Jul. 31, 2011	Jan. 30, 2011
Market Value	$ 173,019	$ 139,323
Adjusted Cost Basis	172,838	139,012
Unrealized Gain	181	311
Agency Securities [Member]
Market Value	53,363	54,747
Adjusted Cost Basis	53,302	54,658
Unrealized Gain	61	89
Corporate Issues [Member]
Market Value	13,656	16,576
Adjusted Cost Basis	13,536	16,354
Unrealized Gain	120	222
Bank Time Deposits [Member]
Market Value	106,000	68,000
Adjusted Cost Basis	$ 106,000	$ 68,000