Loans Receivable and Allowance for Loan Losses: Summary of TDR Loans (Details) - USD ($)	Sep. 30, 2022	Sep. 30, 2021
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR loans included in impaired loans	$ 2,615,000	$ 2,553,000
TDR Loans, commitment to lend additional funds	0	0
Allowance for loan losses	$ 13,703,000	$ 13,469,000

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant