Note 2 - Inventories - Components of Inventory (Details) - USD ($) $ in Thousands		Jun. 30, 2017	Mar. 31, 2017
Raw materials		$ 247	$ 347
Work in process		2,553	2,036
Finished goods (1)	[1]	5,064	5,460
Supplies		117	129
Inventories, net		$ 7,981	$ 7,972

[1] Net of reserve for obsolescence of $33,000 and $3,000 at June 30, 2017 and March 31, 2017, respectively.