Deposits: Schedule of Interest Expense on Deposits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Deposits [Abstract]
NOW checking	$ 605	$ 882	$ 840
Savings	201	188	106
Money market	560	735	1,119
Certificates of deposit	1,647	2,830	2,500
Total	$ 3,013	$ 4,635	$ 4,565

No definition available.

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- Definition

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

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+ Details

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- Definition

Aggregate amount of interest expense on all deposits.

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+ Details

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- Definition

Interest expense incurred on all money market deposits.

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- Definition

Interest expense incurred on all savings account deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)

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- Definition

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

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