Note D - Other Comprehensive (Loss) Income - Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Balance	$ 76,120	$ 75,130	$ 76,084	$ 68,248
Balance	70,749	77,029	70,749	77,029
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(565)	(387)	(491)	(387)
ASU 2018-02 Adjustment			(74)
OCI/OCL before reclassifications
Amounts reclassified from OCI
Tax effect of OCI activity
Net current period OCI/OCL			(74)
Balance	(565)	(387)	(565)	(387)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Balance	213	1,044	783	(191)
ASU 2018-02 Adjustment			(54)
OCI/OCL before reclassifications	990	1,492	1,922	4,221
Amounts reclassified from OCI	(554)	(940)	(2,166)	(2,060)
Tax effect of OCI activity	(101)	(128)	63	(502)
Net current period OCI/OCL	335	424	(235)	1,659
Balance	548	1,468	548	1,468
AOCI Attributable to Parent [Member]
Balance	(352)	657	292	(578)
ASU 2018-02 Adjustment			(128)
OCI/OCL before reclassifications	990	1,492	1,922	4,221
Amounts reclassified from OCI	(554)	(940)	(2,166)	(2,060)
Tax effect of OCI activity	(101)	(128)	63	(502)
Net current period OCI/OCL	335	424	(309)	1,659
Balance	$ (17)	$ 1,081	$ (17)	$ 1,081

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