Loans Receivable and Allowance for Loan Losses: Schedule of Loans receivable and Loans held for sale (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 1,253,618	$ 1,082,290
Undisbursed portion of construction loans in process	103,168	95,224
Deferred loan origination fees	4,321	5,143
Allowance for loan losses	13,703	13,469
Less: Loans in process, Deferred fees and Allowance for loan losses	121,192	113,836
Total loans receivable, net	1,132,426	968,454
Unamortized discounts, loans receivable	267	449
Total mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	1,090,263	931,289
Mortgage loans, one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	176,116	119,935
Mortgage loans, multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	95,025	87,563
Mortgage loans, commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	536,650	470,650
Mortgage loans, construction - custom and owner/builder
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	119,240	109,152
Mortgage loans, construction - speculative one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	12,254	17,813
Mortgage loans, construction - commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	40,364	43,365
Mortgage loans, construction - multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	64,480	52,071
Mortgage loans - construction - land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	19,280	10,804
Mortgage loans, land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	26,854	19,936
Total consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	37,315	35,500
Consumer loans, home equity and second mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	35,187	32,988
Consumer loans, other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	2,128	2,512
Commercial business loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	125,039	74,579
SBA PPP
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	1,001	40,922
Commercial And PPP Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	$ 126,040	$ 115,501

Loans Receivable, Including Loans Held-For-Sale, Excluding Loans in Process and Deferred Fees, Gross

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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 of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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