Nature of Operations (Details) $ / shares in Units, $ in Thousands		3 Months Ended
Mar. 24, 2021 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) Office
Nature of Operations
ESOP shares committed to be released		$ 108
Percentage of shares of the outstanding stock sold		6.97%
Number of full service branch offices \| Office		12
Additional Paid-in capital
Nature of Operations
Cash Acquired from Acquisition	$ 5,400
William Penn Bank
Nature of Operations
Gross proceeds	$ 126,400
William Penn, MHC shares sold in public offering, net of offering costs (in shares) \| shares	12,640,035
Share price \| $ / shares	$ 10.00
Shares outstanding \| shares	776,647
Conversion of existing shares at 3.2585 exchange ratio	3.2585
Percentage of shares sold in offering	8.00%
Percentage of aggregate purchase price of common stock	100.00%
ESOP issued \| shares	881,130
ESOP shares committed to be released	$ 10,100
Ownership percentage held by parent (as a percent)		100.00%

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

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The cash inflow from the additional capital contribution to the entity.

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Aggregate value of stock issued during the period as a result of employee stock ownership plan (ESOP).

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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