Note H - Segment Information (Details Textual) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Mar. 31, 2021	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Number of Reportable Segments				2
Revenue from Contract with Customer, Including Assessed Tax	$ 46,320		$ 25,482	$ 134,129	$ 83,780
Non-US [Member]
Revenue from Contract with Customer, Including Assessed Tax	18,646		12,574	63,595	35,098
UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax	$ 27,674		$ 12,908	$ 70,534	$ 48,682
Products Manufactured by NAIE [Member] | Non-US [Member] | Product Concentration Risk [Member] | Revenue Benchmark [Member]
Concentration Risk, Percentage	65.00%		88.00%	79.00%	90.00%
Products Manufactured by NAIE [Member] | UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax		$ 0	$ 0	$ 0	$ 0