Note 10 - Business Segment Reporting - Sales by Geographic Area (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 29, 2015	Nov. 30, 2014	Nov. 29, 2015	Nov. 30, 2014
CANADA
Segment sales	$ 20.0	$ 17.5	$ 40.4	$ 35.2
TAIWAN, PROVINCE OF CHINA
Segment sales	12.4	9.4	25.4	25.6
CHINA
Segment sales	3.3	2.9	7.3	7.3
INDONESIA
Segment sales	2.5	4.9	3.9	6.5
JAPAN
Segment sales	1.6	2.3	3.6	5.1
PHILIPPINES
Segment sales	0.6	$ 1.8	1.5	$ 2.8
BELGIUM
Segment sales	0.2		1.0
All Other Countries [Member]
Segment sales	$ 3.4	$ 2.8	$ 7.1	$ 5.5