Note 13 - Segment and Geographic - Segment and Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
UNITED STATES
Net Revenues	$ 19,317	$ 21,502	$ 39,450	$ 44,006
FRANCE
Net Revenues	2,302	1,897	4,342	3,749
GERMANY
Net Revenues	8,845	8,026	16,922	16,475
ITALY
Net Revenues	969	909	2,233	2,382
RUSSIAN FEDERATION
Net Revenues	465	2,157	718	2,860
SWEDEN
Net Revenues	574	1,309	1,279	2,594
UNITED KINGDOM
Net Revenues	3,494	5,822	6,714	11,201
Other Europe and the Middle East Regions [Member]
Net Revenues	6,657	6,810	13,091	13,894
CHINA
Net Revenues	20,053	20,480	41,288	40,882
JAPAN
Net Revenues	2,402	2,161	5,724	3,962
KOREA, REPUBLIC OF
Net Revenues	6,089	5,689	12,225	12,128
MALAYSIA
Net Revenues	1,322	1,490	2,564	3,122
SINGAPORE
Net Revenues	3,020	2,913	6,137	6,070
THAILAND
Net Revenues	992	983	2,035	2,027
Other Asia Pacific Regions [Member]
Net Revenues	1,607	1,702	3,091	3,816
INDIA
Net Revenues	909	1,380	2,041	2,629
Other Rest of the World [Member]
Net Revenues	1,240	1,205	2,450	2,718
Net Revenues	$ 80,257	$ 86,435	$ 162,304	$ 174,515