Deposits: Schedule of Interest Expense on Deposits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Deposits [Abstract]
NOW checking	$ 3,561	$ 650	$ 605
Savings	415	230	201
Money market	1,601	767	560
Certificates of deposit	5,725	1,010	1,647
Total	$ 11,302	$ 2,657	$ 3,013

No definition available.

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- Definition

Interest expense incurred on demand deposit accounts that represent borrowings rather than outstanding drafts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

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- Definition

Aggregate amount of interest expense on all deposits.

+ References

+ Details

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- Definition

Interest expense incurred on all money market deposits.

+ References

+ Details

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- Definition

Interest expense incurred on all savings account deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (a)
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)
-Publisher SEC

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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- Definition

The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

+ References

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