Available for Sale Securities - Amortized costs and fair values (Details) - USD ($)	Mar. 31, 2020	Jun. 30, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 21,909,742	$ 20,339,563
Gross Unrealized Gains	495,324	261,169
Gross Unrealized Losses	26,244	58,614
Fair Value	22,378,822	20,542,118
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	19,703,101	18,719,370
Gross Unrealized Gains	428,159	217,627
Gross Unrealized Losses	26,244	58,614
Fair Value	20,105,016	18,878,383
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,406,641	1,065,193
Gross Unrealized Gains	41,589	40,945
Gross Unrealized Losses	0	0
Fair Value	1,448,230	1,106,138
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	800,000	555,000
Gross Unrealized Gains	25,576	2,597
Gross Unrealized Losses	0	0
Fair Value	$ 825,576	$ 557,597

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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