Note 13 - Retirement Benefits - Funded Status for Pension Plan (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jun. 30, 2020
Prepaid benefit cost	$ 5,161	$ 4,663
Current liabilities	(552)	(503)
Non-current liabilities	(65,246)	(77,172)
Net amount recognized	$ (60,637)	$ (73,012)

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant