Fair Value Measurements: Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023
Fair value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments in equity securities	$ 866	$ 811
Recorded Amount
Fair value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	164,728	128,721
CDs held for investment	10,209	15,188
Investment securities	244,354	311,989
Investments in equity securities	866	811
FHLB stock	2,037	3,602
Other investments	3,000	3,000
Loans held for sale		400
Loans receivable, net	1,421,523	1,302,305
Accrued interest receivable	6,990	6,004
Certificates of deposit	368,308	300,100
FHLB borrowings	20,000	35,000
Accrued interest payable	2,132	1,397
Fair Value
Fair value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	164,728	128,721
CDs held for investment	10,209	15,188
Investment securities	238,264	295,538
Investments in equity securities	866	811
FHLB stock	2,037	3,602
Other investments	3,000	3,000
Loans held for sale		407
Loans receivable, net	1,387,642	1,246,538
Accrued interest receivable	6,990	6,004
Certificates of deposit	368,312	297,542
FHLB borrowings	20,035	34,747
Accrued interest payable	2,132	1,397
Fair Value \| Fair Value, Inputs, Level 1
Fair value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	164,728	128,721
CDs held for investment	10,209	15,188
Investment securities	146,141	161,538
Investments in equity securities	866	811
FHLB stock	2,037	3,602
Other investments	3,000	3,000
Loans held for sale		407
Loans receivable, net	0	0
Accrued interest receivable	6,990	6,004
Certificates of deposit	0	0
FHLB borrowings	0	0
Accrued interest payable	2,132	1,397
Fair Value \| Fair Value, Inputs, Level 2
Fair value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
CDs held for investment	0	0
Investment securities	92,123	134,000
Investments in equity securities	0	0
FHLB stock	0	0
Other investments	0	0
Loans held for sale		0
Loans receivable, net	0	0
Accrued interest receivable	0	0
Certificates of deposit	0	0
FHLB borrowings	0	0
Accrued interest payable	0	0
Fair Value \| Fair Value, Inputs, Level 3
Fair value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
CDs held for investment	0	0
Investment securities	0	0
Investments in equity securities	0	0
FHLB stock	0	0
Other investments	0	0
Loans held for sale		0
Loans receivable, net	1,387,642	1,246,538
Accrued interest receivable	0	0
Certificates of deposit	368,312	297,542
FHLB borrowings	20,035	34,747
Accrued interest payable	$ 0	$ 0

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

+ References

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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.

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- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount of investments classified as other.

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