Note 11 - Stock-based Compensation - Unrecognized Stock-based Compensation Expense Related to Stock Options and RSUs (Details) $ in Thousands	9 Months Ended
	Jan. 01, 2017 USD ($)
Unrecognized stock-based compensation expense	$ 10,074
Employee Stock Option [Member]
Unrecognized stock-based compensation expense	$ 4,887
Weighted Average Remaining Recognition Period (Year)	2 years 215 days
Restricted Stock Units (RSUs) [Member]
Unrecognized stock-based compensation expense	$ 4,557
Weighted Average Remaining Recognition Period (Year)	2 years 211 days
Performance-based RSUs [Member]
Unrecognized stock-based compensation expense	$ 630
Weighted Average Remaining Recognition Period (Year)	1 year 251 days