Fair Value of Financial Assets (Tables)
6 Months Ended
Jul. 28, 2012
Fair Value of Financial Assets and Liabilities [Abstract]  
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]
The following table presents the Company's assets measured at fair value on a recurring basis as of July 28, 2012 and January 28, 2012, aggregated by the level in the fair value hierarchy within which those measurements fall.
 
 
July 28, 2012
 
Level 1
Level 2
Level 3
 
(in thousands)
U.S. treasury securities funds
$
106,664

$

$

 
 
 
January 28, 2012
 
Level 1
Level 2
Level 3
 
(in thousands)
U.S. treasury securities funds
$
131,543

$

$