Note 15 - Segment and Geographic Information - Long-lived Assets By Geographic Area (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Property, plant and equipment, net	$ 42,240	$ 42,623	$ 42,545
UNITED STATES
Property, plant and equipment, net	25,284	26,792	27,740
GERMANY
Property, plant and equipment, net	15,594	14,506	13,228
Other Geographic Regions [Member]
Property, plant and equipment, net	$ 1,362	$ 1,325	$ 1,577