Restructuring (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 27, 2014	Jan. 26, 2014	Apr. 28, 2013
Restructuring Reserve [Roll Forward]
Balance at January 26, 2014	$ 2,632
Charges	1,001	3,100	0
Cash payments	(2,803)
Balance at April 27, 2014	830	2,632
One-time employee termination benefits [Member]
Restructuring Reserve [Roll Forward]
Balance at January 26, 2014	1,387
Charges	378
Cash payments	(1,568)
Balance at April 27, 2014	197
Contract commitments [Member]
Restructuring Reserve [Roll Forward]
Balance at January 26, 2014	1,245
Charges	623
Cash payments	(1,235)
Balance at April 27, 2014	$ 633