Investments (Maturities of Investment Securities) (Details) (USD $) In Thousands	Apr. 30, 2011	Jan. 29, 2011	May 01, 2010
Investments
Maturing in one year or less at cost basis	$ 3,212
Maturing after one year through five years at cost basis	5,070
Maturing after five years through ten years at cost basis	6,438
Total cost basis	14,720	16,535	17,494
Maturing in one year or less at estimated fair value	3,275
Maturing after one year through five years at estimated fair value	5,408
Maturing after five through ten years at estimated fair value	6,783
Total estimated fair value	$ 15,466	$ 17,286	$ 17,798