Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Loans - Summary of loans (Details) - USD ($)	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 194,757,902		$ 187,900,474	$ 158,582,539
Deferred loan fees	(76,455)		(75,552)
Allowance for loan losses	(2,059,471)	$ (2,058,869)	(2,195,050)	(2,188,643)	$ (2,187,306)	$ (2,186,182)
Loans, net	192,621,976		185,629,872
Commercial real estate [Member] \| Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	85,612,836		80,603,153	63,032,800
Allowance for loan losses	(1,285,009)	(1,564,021)	(1,591,644)	(1,288,427)	(1,223,850)	(1,036,301)
Commercial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total loans	100,856,113		99,964,364
Commercial [Member] \| Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	85,612,836		80,603,153
Commercial [Member] \| Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total loans	7,830,296		8,778,723	8,901,181
Allowance for loan losses	(21,338)	(27,398)	(32,701)	(49,009)	(68,497)	(157,533)
Commercial [Member] \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Total loans	7,412,981		10,582,488	8,098,343
Allowance for loan losses	(17,606)	(24,791)	(55,029)	(47,780)	(50,646)	(59,649)
Residential [Member] \| One-to-four-family residential
Loans and Leases Receivable Disclosure [Line Items]
Total loans	56,704,945		51,890,948	51,680,119
Allowance for loan losses	(208,286)	(222,284)	(263,951)	(341,911)	(356,257)	(409,395)
Residential [Member] \| Multi-family real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	35,113,319		33,944,903	24,615,280
Allowance for loan losses	(195,757)	(216,133)	(233,371)	(121,353)	(86,482)	(134,216)
Consumer Loans [Member] \| Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	2,083,525		2,100,259	2,254,816
Allowance for loan losses	$ (603)	$ (620)	$ (601)	$ (5,532)	$ (5,918)	$ (4,896)