Loans Receivable and Allowance for Loan Losses: Schedule of Loans receivable and Loans held for sale (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 1,426,558	$ 1,253,618
Undisbursed portion of construction loans in process	103,194	103,168
Deferred loan origination fees	5,242	4,321
Allowance for loan losses	15,817	13,703
Less: Loans in process, Deferred fees and Allowance for loan losses	124,253	121,192
Total loans receivable, net	1,302,305	1,132,426
Unamortized discounts, loans receivable	192	267
Total mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	1,249,237	1,090,263
Mortgage loans, one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	253,227	176,116
Mortgage loans, multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	127,176	95,025
Mortgage loans, commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	568,265	536,650
Mortgage loans, construction - custom and owner/builder
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	129,699	119,240
Mortgage loans, construction - speculative one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	17,099	12,254
Mortgage loans, construction - commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	51,064	40,364
Mortgage loans, construction - multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	57,140	64,480
Mortgage loans - construction - land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	18,841	19,280
Mortgage loans, land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	26,726	26,854
Total consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	41,053	37,315
Consumer loans, home equity and second mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	38,281	35,187
Consumer loans, other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	2,772	2,128
Commercial business loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	135,802	125,039
SBA PPP
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	466	1,001
Commercial And PPP Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
SBA Paycheck Protection Program ("PPP")	$ 136,268	$ 126,040

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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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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