Investments And Restricted Investments (Investments And Restricted Investments) (Details) (USD $) In Thousands	Jul. 30, 2011	Jan. 29, 2011	Jul. 31, 2010
Total investments measured at fair value	$ 13,693	$ 17,286	$ 21,026
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Investments [Member]
Total investments measured at fair value
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Investments [Member] | Corporate Securities [Member]
Total investments measured at fair value
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Investments [Member] | U.S. Government And Agency Securities [Member]
Total investments measured at fair value		8,031	10,744
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Investments [Member] | Mortgage-Backed Securities [Member]
Total investments measured at fair value
Significant Other Observable Inputs (Level 2) [Member] | Investments [Member]
Total investments measured at fair value	7,202
Significant Other Observable Inputs (Level 2) [Member] | Investments [Member] | Corporate Securities [Member]
Total investments measured at fair value	6,298	8,062	8,784
Significant Other Observable Inputs (Level 2) [Member] | Investments [Member] | U.S. Government And Agency Securities [Member]
Total investments measured at fair value
Significant Other Observable Inputs (Level 2) [Member] | Investments [Member] | Mortgage-Backed Securities [Member]
Total investments measured at fair value	904	1,193	1,498
Investments [Member]
Total investments measured at fair value	7,202
Investments [Member] | Corporate Securities [Member]
Total investments measured at fair value	6,298	8,062	8,784
Investments [Member] | Corporate Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value
Investments [Member] | U.S. Government And Agency Securities [Member]
Total investments measured at fair value		8,031	10,744
Investments [Member] | U.S. Government And Agency Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value
Investments [Member] | Mortgage-Backed Securities [Member]
Total investments measured at fair value	904	1,193	1,498
Investments [Member] | Mortgage-Backed Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value
Investments [Member] | Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Restricted Investments [Member]
Total investments measured at fair value	5,019
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Restricted Investments [Member] | Corporate Securities [Member]
Total investments measured at fair value
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Restricted Investments [Member] | U.S. Government And Agency Securities [Member]
Total investments measured at fair value	5,019
Significant Other Observable Inputs (Level 2) [Member] | Restricted Investments [Member]
Total investments measured at fair value	1,472
Significant Other Observable Inputs (Level 2) [Member] | Restricted Investments [Member] | Corporate Securities [Member]
Total investments measured at fair value	1,472
Significant Other Observable Inputs (Level 2) [Member] | Restricted Investments [Member] | U.S. Government And Agency Securities [Member]
Total investments measured at fair value
Restricted Investments [Member]
Total investments measured at fair value	6,491
Restricted Investments [Member] | Corporate Securities [Member]
Total investments measured at fair value	1,472
Restricted Investments [Member] | Corporate Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value
Restricted Investments [Member] | U.S. Government And Agency Securities [Member]
Total investments measured at fair value	5,019
Restricted Investments [Member] | U.S. Government And Agency Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value
Restricted Investments [Member] | Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Total investments measured at fair value	5,019	8,031	10,744
Significant Other Observable Inputs (Level 2) [Member]
Total investments measured at fair value	8,674	9,255	10,282
Significant Unobservable Inputs (Level 3) [Member]
Total investments measured at fair value