Fair Value Measurements: Fair Value Measurements, Nonrecurring, Valuation Techniques (Details) - Nonrecurring - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	Jun. 30, 2023	Sep. 30, 2022
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Assets, estimated fair value, nonrecurring	$ 122	$ 123
Impaired loans \| Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Assets, estimated fair value, nonrecurring	$ 122	$ 123

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-30

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-31

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-32

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