Loans and Allowance for Loan Losses, Impaired Loans By Loan Portfolio Class (Details) - USD ($)	3 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Loans and Allowance for Loan Losses [Abstract]
Threshold principal amount of nonaccrual loans evaluated individually for impairment	$ 100,000
With no related allowance recorded [Abstract]
Recorded investment	1,256,000		$ 970,000
Unpaid principal	1,256,000		970,000
Average recorded investment	892,000	$ 1,263,000
Interest income recognized	3,000	6,000
With an allowance recorded [Abstract]
Recorded investment	4,814,000		5,325,000
Unpaid principal	4,814,000		5,325,000
Related allowance	410,000		391,000
Average recorded investment	5,149,000	1,917,000
Interest income recognized	58,000	9,000
Total impaired [Abstract]
Recorded investment	6,070,000		6,295,000
Unpaid principal	6,070,000		6,295,000
Related allowance	410,000		391,000
Average recorded investment	6,041,000	3,180,000
Interest income recognized	61,000	15,000
Residential Real Estate [Member] \| Residential Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded investment	236,000		370,000
Unpaid principal	236,000		370,000
Average recorded investment	221,000	402,000
Interest income recognized	0	5,000
With an allowance recorded [Abstract]
Recorded investment	716,000		723,000
Unpaid principal	716,000		723,000
Related allowance	102,000		103,000
Average recorded investment	718,000	1,385,000
Interest income recognized	5,000	5,000
Total impaired [Abstract]
Recorded investment	952,000		1,093,000
Unpaid principal	952,000		1,093,000
Related allowance	102,000		103,000
Average recorded investment	939,000	1,787,000
Interest income recognized	5,000	10,000
Residential Real Estate [Member] \| Multi-family [Member]
With no related allowance recorded [Abstract]
Recorded investment			0
Unpaid principal			0
Average recorded investment		121,000
Interest income recognized		0
With an allowance recorded [Abstract]
Related allowance			0
Total impaired [Abstract]
Recorded investment			0
Unpaid principal			0
Related allowance			0
Average recorded investment		121,000
Interest income recognized		0
Commercial Real Estate [Member] \| Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded investment	783,000		281,000
Unpaid principal	783,000		281,000
Average recorded investment	445,000	335,000
Interest income recognized	3,000	1,000
With an allowance recorded [Abstract]
Recorded investment	450,000		945,000
Unpaid principal	450,000		945,000
Related allowance	54,000		58,000
Average recorded investment	780,000	0
Interest income recognized	10,000	0
Total impaired [Abstract]
Recorded investment	1,233,000		1,226,000
Unpaid principal	1,233,000		1,226,000
Related allowance	54,000		58,000
Average recorded investment	1,225,000	335,000
Interest income recognized	13,000	1,000
Commercial Real Estate [Member] \| Construction [Member]
With an allowance recorded [Abstract]
Recorded investment	102,000		102,000
Unpaid principal	102,000		102,000
Related allowance	1,000		1,000
Average recorded investment	102,000	102,000
Interest income recognized	0	0
Total impaired [Abstract]
Recorded investment	102,000		102,000
Unpaid principal	102,000		102,000
Related allowance	1,000		1,000
Average recorded investment	102,000	102,000
Interest income recognized	0	0
Consumer Loan [Member] \| Home Equity [Member]
With no related allowance recorded [Abstract]
Recorded investment	128,000		224,000
Unpaid principal	128,000		224,000
Average recorded investment	128,000	128,000
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	321,000		321,000
Unpaid principal	321,000		321,000
Related allowance	45,000		73,000
Average recorded investment	321,000	430,000
Interest income recognized	3,000	4,000
Total impaired [Abstract]
Recorded investment	449,000		545,000
Unpaid principal	449,000		545,000
Related allowance	45,000		73,000
Average recorded investment	449,000	558,000
Interest income recognized	3,000	4,000
Commercial Loans [Member]
With no related allowance recorded [Abstract]
Recorded investment	109,000		95,000
Unpaid principal	109,000		95,000
Average recorded investment	98,000	277,000
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	3,225,000		3,234,000
Unpaid principal	3,225,000		3,234,000
Related allowance	208,000		156,000
Average recorded investment	3,228,000	0
Interest income recognized	40,000	0
Total impaired [Abstract]
Recorded investment	3,334,000		3,329,000
Unpaid principal	3,334,000		3,329,000
Related allowance	208,000		$ 156,000
Average recorded investment	3,326,000	277,000
Interest income recognized	$ 40,000	$ 0

The threshold principal amount of nonaccrual loans evaluated individually for impairment.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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