Note 18 - Quarterly Financial Data (Unaudited) (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Operating Income (Loss), Total	$ 2,800	$ (5,303)	$ 11,221	$ 5,518
Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash, Total	16,700	$ 16,823	$ 1,000	$ 876
Fair Value, Nonrecurring [Member]
Restructuring Costs and Asset Impairment Charges, Total	$ 8,100

The net result for the period of deducting operating expenses from operating revenues.

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Amount of noncash expense (reversal of expense) for pension and other postretirement benefits.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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