Note 12 - Retirement Benefits (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 252	$ 277	$ 751	$ 808
Pension Plan [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 2,018,000

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration