Note N - Pension and Other Postretirement Benefit Plans - Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Pension Plan [Member]
Net loss	$ 4,770	$ 8,098
Amortization of transition asset	(35)	(34)
Amortization of prior service (cost) benefit	(45)	(64)
Amortization of net (loss) gain	(2,978)	(2,711)
Total recognized in other comprehensive income	1,712	5,078
Net periodic benefit cost	2,120	2,381
Total recognized in net periodic benefit cost and other comprehensive income	3,832	7,459
Prior service cost		(211)
Other Postretirement Benefits Plan [Member]
Net loss	211	18
Amortization of transition asset
Amortization of prior service (cost) benefit	275	275
Amortization of net (loss) gain
Total recognized in other comprehensive income	486	293
Net periodic benefit cost	(38)	48
Total recognized in net periodic benefit cost and other comprehensive income	$ 448	341
Prior service cost