Note 3 - Loans - Loans by Class Modified as Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 31, 2019 USD ($)	Mar. 31, 2018	Jun. 30, 2018	Jun. 30, 2017 USD ($)
Financing Receivable, Modifications, Number of Contracts	0	1	0	0	3
Pre-Modification Outstanding Recorded Investment		$ 161			$ 1,030
Post-Modification Outstanding Recorded Investment		$ 59			$ 1,030
Commercial Real Estate Portfolio Segment [Member] \| Other Commercial Real Estate Loans [Member]
Financing Receivable, Modifications, Number of Contracts		1			1
Pre-Modification Outstanding Recorded Investment		$ 161			$ 512
Post-Modification Outstanding Recorded Investment		$ 59			$ 512

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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