Goodwill and Intangible Assets - Schedule of Additions to Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 25, 2015
Finite-lived Intangible Assets [Roll Forward]
Beginning gross carrying amount	$ 169,048	$ 185,997
Purchased intangible assets	12,000	1,100
Acquired intangible assets		1,430
Transfers from in-process research and development	4,000
Decrease in gross carrying value of due to impairment of finite-lived intangible a		(19,479)
Other	(108)
Ending gross carrying value	$ 184,940	$ 169,048