Note H - Segment Information (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Number of Reportable Segments	2
Revenue from Contract with Customer, Including Assessed Tax	$ 25,482	$ 35,455	$ 83,780	$ 108,030
Non-US [Member]
Revenue from Contract with Customer, Including Assessed Tax	12,574	19,233	35,098	55,613
UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax	$ 12,908	$ 16,222	$ 48,682	$ 52,417
Products Manufactured by NAIE [Member] | Non-US [Member] | Revenue Benchmark [Member] | Product Concentration Risk [Member]
Concentration Risk, Percentage	88.00%	74.00%	90.00%	78.00%
Products Manufactured by NAIE [Member] | UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0	$ 0	$ 0