Note 5 - Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Jun. 30, 2019
Property and equipment, gross		$ 9,183	$ 8,979
Less accumulated depreciation		(7,447)	(7,370)
Property and equipment, net		1,736	1,609
Land [Member]
Property and equipment, gross		366	366
Equipment [Member]
Property and equipment, gross		3,873	3,825
Leasehold Improvements [Member]
Property and equipment, gross		4,143	4,143
Other [Member]
Property and equipment, gross	[1]	$ 801	$ 645

[1] Includes plant and equipment not placed in service which are items that meet the capitalization threshold or which management believes will meet the threshold at the time of completion and which have yet to be placed into service as of the date of the balance sheet, and therefore, no depreciation expense has been recognized. Also included at December 31, 2019 and June 30, 2019 are costs associated with advance planning and design work on the Company’s new production facility of $207,000.