Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	9 Months Ended	12 Months Ended
Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)
Number of Reportable Segments	1	1
Cash Reserve Deposit Required and Made Federal Reserve Banks		$ 329	$ 304
Bank Owned Life Insurance		19,776	19,728
Cash Surrender Value of Life Insurance	$ 9,538	9,335	$ 9,065
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect
Retained Earnings [Member]
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect		(14)
AOCI Attributable to Parent [Member]
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect		$ 14
Software and Software Development Costs [Member]
Property, Plant and Equipment, Useful Life		3 years
Building [Member]
Property, Plant and Equipment, Useful Life		39 years 182 days

Cash reserve deposit required and made with Federal Reserve Banks pursuant to Federal Reserve Board regulations.

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Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

+ References

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- Definition

The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6812-107765

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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