Note 9 - Commitments and Contingencies (Details Textual) $ in Millions		1 Months Ended	3 Months Ended			6 Months Ended		12 Months Ended
	Mar. 08, 2013 USD ($)	Aug. 31, 2015 USD ($)	Aug. 01, 2015 USD ($)	Aug. 02, 2014 USD ($)	May. 03, 2014 USD ($)	Aug. 01, 2015 USD ($)	Aug. 02, 2014 USD ($)	Feb. 01, 2014 USD ($)
Design Tool Licences [Member]
Purchase Commitment, Remaining Minimum Amount Committed			$ 4.1			$ 4.1
Long-term Purchase Commitment, Amount						3.0		$ 12.9
Cost of Sales [Member]
Direct Operating Cost, Royalty Expense			1.3	$ 0.5		2.1	$ 1.1
Additional Expenditures Incurred but Not yet Paid			0.1			0.1
Selling and Marketing Expense [Member]
Loss Contingency, Loss in Period					$ 0.1
Additional After Timely First Milestone [Member]
Revenue Recognition, Milestone Method, Revenue Recognized	$ 5.0
The Buyer Vs. the Entity [Member] | Subsequent Event [Member]
Litigation Settlement, Amount		$ 5.0
Purchase Commitment, Remaining Minimum Amount Committed			$ 35.3			35.3
Proceeds from Grantors						$ 5.2
Percentage of Royalties			4.50%			4.50%
Accrued Royalties			$ 1.1			$ 1.1
Number of Employees Transferred	21
Loss Contingency Accrual					$ 0.2