Note F - Economic Dependency - Substantial Net Sales to Certain Customers (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2018		Dec. 31, 2017
Net sales	$ 36,043	$ 33,335		$ 72,575		$ 61,409
Customer Concentration Risk [Member] | Sales Revenue, Goods, Net [Member]
Net sales	27,836	23,213		48,753		39,531
Customer Concentration Risk [Member] | Sales Revenue, Goods, Net [Member] | Customer 1 [Member]
Net sales	17,750	19,134		38,827		32,292
Customer Concentration Risk [Member] | Sales Revenue, Goods, Net [Member] | Customer 2 [Member]
Net sales	6,196	4,079		9,926		7,239
Customer Concentration Risk [Member] | Sales Revenue, Goods, Net [Member] | Customer 3 [Member]
Net sales	$ 3,890		[1]		[1]		[1]

[1] Sales were less than 10% of the respective period's consolidated net sales.