Note 9 - Intangible Assets - Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Mar. 31, 2016
Gross Intangible Assets	$ 40,615	$ 40,945
Accumulated Impairment	1,391
Accumulated Amortization	35,646	33,338
Net Intangible Assets	3,578	7,607
Developed Technology Rights [Member]
Gross Intangible Assets	17,197	17,309
Accumulated Impairment	265
Accumulated Amortization	13,481	11,639
Net Intangible Assets	3,451	5,670
Customer Relationships [Member]
Gross Intangible Assets	13,464	13,520
Accumulated Impairment	123
Accumulated Amortization	13,341	12,961
Net Intangible Assets		559
In Process Research and Development [Member]
Gross Intangible Assets	1,056	1,188
Accumulated Impairment	1,003
Accumulated Amortization	53
Net Intangible Assets		1,188
Order or Production Backlog [Member]
Gross Intangible Assets	7,310	7,329
Accumulated Impairment
Accumulated Amortization	7,310	7,329
Net Intangible Assets
Other Intangible Assets [Member]
Gross Intangible Assets	1,588	1,599
Accumulated Impairment
Accumulated Amortization	1,461	1,409
Net Intangible Assets	$ 127	$ 190