v3.23.1

Note 6 - Investment Securities (Details Textual)	3 Months Ended	6 Months Ended
Note 6 - Investment Securities (Details Textual)	Mar. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)
Proceeds From Calls Of Available For Sale Securities		$ 1,000,000.0	$ 945,000
Proceeds From Partial Calls Of Available For Sale Securities		10,000	10,000
Proceeds from Sale of Held-to-Maturity Securities		2,000,000.0	2,500,000
Payments to Acquire Investments	$ 0	0
Deposit Liabilities, Collateral Issued, Financial Instruments	33.8	33.8		$ 11,900,000
Carrying Value Of Investment Securities Pledged Against Hedge	0	0		0
Deposit Liabilities Collateral Short Term Borrowings Issued Financial Instruments	$ 0	$ 0		$ 0
Mutual Fund [Member]
Proceeds from Sale and Maturity, Debt Security, Trading, and Equity Security, FV-NI, Held-for-Investment			$ 250,000
Corporate Debt Securities [Member]
Number Of Portfolio Investments	13	13
US States and Political Subdivisions Debt Securities [Member]
Number Of Portfolio Investments	11	11
US Government Agencies Debt Securities [Member]
Number Of Portfolio Investments	1	1
US Treasury Securities [Member]
Number Of Portfolio Investments	1	1
Collateralized Mortgage-Backed Securities [Member]
Number Of Portfolio Investments	1	1
Single Issuer Trust Preferred Security [Member]
Number Of Portfolio Investments	1	1

Carrying value of investment securities Pledged against hedge.

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- Definition

Deposit Liabilities Collateral Short Term Borrowings Issued Financial Instruments.

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- Definition

Number of portfolio investments.

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- Definition

Proceeds from calls of available for sale securities.

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- Definition

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
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The cash inflow associated with the sale, maturities, repayments and calls of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

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The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
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-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-11

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MALVERN BANCORP, INC. 10-Q