Loans Receivable and Allowance for Loan Losses: Schedule of Loans receivable and Loans held for sale (Details) - USD ($)	Sep. 30, 2024	Sep. 30, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 1,514,304,000	$ 1,426,558,000
Undisbursed portion of construction loans in process	69,878,000	103,194,000
Deferred loan origination fees	5,425,000	5,242,000
Allowance for credit losses	17,478,000	15,817,000
Less: Loans in process, Deferred fees and Allowance for loan losses	92,781,000	124,253,000
Total loans receivable, net	1,421,523,000	1,302,305,000
Unamortized discounts, loans receivable	155,000	192,000
Total mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	1,324,259,000	1,249,237,000
Mortgage loans, one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	299,123,000	253,227,000
Mortgage loans, multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	177,350,000	127,176,000
Mortgage loans, commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	599,219,000	568,265,000
Mortgage loans, construction - custom and owner/builder
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	132,101,000	129,699,000
Mortgage loans, construction - speculative one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	11,495,000	17,099,000
Mortgage loans, construction - commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	29,463,000	51,064,000
Mortgage loans, construction - multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	28,401,000	57,140,000
Mortgage loans - construction - land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	17,741,000	18,841,000
Mortgage loans, land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	29,366,000	26,726,000
Total consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	51,042,000	41,053,000
Consumer loans, home equity and second mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	47,913,000	38,281,000
Consumer loans, other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	3,129,000	2,772,000
Commercial business loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	138,743,000	135,802,000
SBA PPP
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	260,000	466,000
Commercial And PPP Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	$ 139,003,000	$ 136,268,000

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

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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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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