Restructuring (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Oct. 26, 2014	Apr. 27, 2014	Oct. 27, 2013	Oct. 26, 2014	Oct. 27, 2013
Restructuring Reserve [Roll Forward]
Balance at January 26, 2014		$ 2,632		$ 2,632
Charges	0	1,000	0	1,001	0
Cash payments				(3,405)
Reclassifications				(115)
Balance at October 26, 2014	113			113
One-time employee termination benefits [Member]
Restructuring Reserve [Roll Forward]
Balance at January 26, 2014		1,387		1,387
Charges				378
Cash payments				(1,719)
Reclassifications				0
Balance at October 26, 2014	46			46
Contract commitments [Member]
Restructuring Reserve [Roll Forward]
Balance at January 26, 2014		1,245		1,245
Charges				623
Cash payments				(1,686)
Reclassifications				(115)
Balance at October 26, 2014	$ 67			$ 67