Loans and Allowance for Loan Losses - Major classifications (Details) - USD ($)	6 Months Ended	12 Months Ended
Dec. 31, 2021	Jun. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 235,502,457	$ 216,832,440		$ 234,053,332
Less: allowance for loan losses	(1,487,823)	(1,412,489)	$ (1,462,889)	(1,403,491)	$ (1,353,484)	$ (1,353,427)
Total	234,014,634	215,419,951		232,649,841
Deferred loan origination fees	131,000	99,000
1-4 Family Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	72,853,855	72,011,570		85,247,077
Less: allowance for loan losses	(354,251)	(326,408)	(339,916)	(318,772)	(335,391)	(356,434)
Total	72,499,604	71,685,162		84,928,305
1-4 Family Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	25,508,136	22,368,557		22,592,637
Less: allowance for loan losses	(127,541)	(115,645)	(100,119)	(87,352)	(75,827)	(77,220)
Total	25,380,595	22,252,912		22,505,285
Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Total loans	100,199,616	91,876,323		88,769,856
Less: allowance for loan losses	(526,048)	(459,382)	(484,106)	(399,465)	(350,641)	(286,665)
Total	99,673,568	91,416,941		88,370,391
Commercial Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	6,135,242	6,405,226		6,474,308
Less: allowance for loan losses	(106,166)	(99,851)	(101,647)	(86,450)	(75,184)	(95,711)
Total	6,029,076	6,305,375		6,387,858
Commercial Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	14,046,851	14,182,106		19,679,205
Less: allowance for loan losses	(179,098)	(230,459)	(218,697)	(340,647)	(328,902)	(312,670)
Total	13,867,753	13,951,647		19,338,558
Construction, Land, Development
Loans and Leases Receivable Disclosure [Line Items]
Total loans	9,760,179	2,458,461		3,460,986
Less: allowance for loan losses	(46,361)	(11,063)	(36,317)	(11,248)	(10,859)	(13,795)
Total	9,713,818	2,447,398		3,449,738
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	6,998,578	7,530,197		7,829,263
Less: allowance for loan losses	(54,613)	(66,523)	$ (61,871)	(86,852)	$ (89,941)	$ (97,312)
Total	$ 6,943,965	$ 7,463,674		$ 7,742,411

The net increase(decrease) in interest income during the period representing the allocation of deferred loan origination fees less deferred loan origination costs using the effective interest method over the term of the debt arrangement to which they pertain taking into account the effect of prepayments.

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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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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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