Note 4 - Loans (Details Textual) xbrli-pure in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2019 USD ($)
Interest Receivable	$ 862		$ 862		$ 891
Financing Receivable, Nonaccrual	427		427		785
Financing Receivable, Troubled Debt Restructuring	689		689		725
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	0		0		9
Troubled Debt Restructuring, Debtor, Subsequent Periods, Contingent Payments, Amount, Total	$ 9		$ 9		9
Financing Receivable, Modifications, Number of Contracts	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 0	$ 0	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0	0	0
Threshold Amount of Loans Outstanding to Perform Credit Analysis	$ 100		$ 100
Non-accrual Loans [Member]
Financing Receivable, Nonaccrual	418		418		507
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Nonaccrual	$ 9		$ 9
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Nonaccrual					198
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Nonaccrual					$ 80

The threshold amount of loans outstanding balance that will trigger the credit analysis.

No definition available.

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- Definition

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

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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- Definition

Amount of financing receivable on nonaccrual status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18794-111554

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- Definition

Amount of restructured debt contingently payable based on the occurrence of future events or circumstances.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 60
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6402221&loc=d3e15765-112638

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