Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Percentage of vesting of award under share-based payment arrangement.

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Note 12 - Equity Based Incentive Compensation Plan (Details Textual) - USD ($)	3 Months Ended			6 Months Ended
	Mar. 31, 2023	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)					2,336
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	6,000			6,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)			0		0
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	4,200			6,958
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)	2,336		1,120		1,216
Unrestricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	3,979		0	3,979	0
Malvern Bancorp Inc 2014 Long Term Incentive Compensation Plan Member
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	400,000	400,000		400,000
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	266,839	266,839		266,839
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)				6,000	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period (in shares)		0		0	2,000
Malvern Bancorp Inc 2014 Long Term Incentive Compensation Plan Member \| Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Expense	$ 7,000		$ 9,000	$ 16,000	$ 18,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	68,000	$ 68,000		$ 68,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				3 years 1 month 6 days
Malvern Bancorp Inc 2014 Long Term Incentive Compensation Plan Member \| Restricted Stock [Member]
Share-Based Payment Arrangement, Expense	43,000		$ 47,000	$ 86,000	$ 86,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				10,937	5,131
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)				(0)	2,336
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	453,000	$ 453,000		$ 453,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				3 years 3 months 10 days
Malvern Bancorp Inc 2014 Long Term Incentive Compensation Plan Member \| Unrestricted Stock [Member]
Share-Based Payment Arrangement, Expense	$ 71,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	3,979
Malvern Bancorp Inc 2014 Long Term Incentive Compensation Plan Member \| Granted in 2022 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage				20.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period (Year)				1 year