Note 5 - Intangible Assets (Details Textual) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jul. 29, 2017	Jul. 29, 2017	Jan. 28, 2017
Finite-Lived Intangible Assets, Net	$ 27,199	$ 27,199	$ 30,744
Purchased Intellectual Property - Not Yet Deployed [Member]
Finite-Lived Intangible Assets, Net	11,700	11,700	$ 12,009
Purchased Intellectual Property - Not Yet Deployed [Member] | Fiscal 2018 Plan [Member]
Impairment of Intangible Assets, Finite-lived	0	3,000
Purchased Intellectual Property - Not Yet Deployed [Member] | Collaborative Arrangement, Product [Member] | Telechips Inc [Member]
Finite-Lived Intangible Assets, Net	$ 1,000	$ 1,000