Loans, Impaired Loans By Loan Portfolio Class (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Loans [Abstract]
Threshold principal amount of nonaccrual loans evaluated individually for impairment	$ 100
With no related allowance recorded [Abstract]
Recorded investment	970	$ 1,608
Unpaid principal	970	1,608
Average recorded investment	1,064	1,565
Interest income recognized	26	85
With an allowance recorded [Abstract]
Recorded investment	5,325	1,662
Unpaid principal	5,325	1,662
Related allowance	391	228
Average recorded investment	2,796	1,931
Interest income recognized	189	84
Total impaired [Abstract]
Recorded investment	6,295	3,270
Unpaid principal	6,295	3,270
Related allowance	391	228
Average recorded investment	3,860	3,496
Interest income recognized	215	169
Residential Real Estate [Member] \| Residential Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded investment	370	868
Unpaid principal	370	868
Average recorded investment	387	719
Interest income recognized	14	70
With an allowance recorded [Abstract]
Recorded investment	723	995
Unpaid principal	723	995
Related allowance	103	127
Average recorded investment	971	1,184
Interest income recognized	32	47
Total impaired [Abstract]
Recorded investment	1,093	1,863
Unpaid principal	1,093	1,863
Related allowance	103	127
Average recorded investment	1,358	1,903
Interest income recognized	46	117
Residential Real Estate [Member] \| Multi-family [Member]
With no related allowance recorded [Abstract]
Recorded investment	0	123
Unpaid principal	0	123
Average recorded investment	30	42
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	0	0
Unpaid principal	0	0
Related allowance	0	0
Average recorded investment	0	54
Interest income recognized	0	1
Total impaired [Abstract]
Recorded investment	0	123
Unpaid principal	0	123
Related allowance	0	0
Average recorded investment	30	96
Interest income recognized	0	1
Commercial Real Estate [Member] \| Real Estate Mortgage [Member]
With no related allowance recorded [Abstract]
Recorded investment	281	344
Unpaid principal	281	344
Average recorded investment	313	499
Interest income recognized	4	14
With an allowance recorded [Abstract]
Recorded investment	945	0
Unpaid principal	945	0
Related allowance	58	0
Average recorded investment	236	26
Interest income recognized	4	3
Total impaired [Abstract]
Recorded investment	1,226	344
Unpaid principal	1,226	344
Related allowance	58	0
Average recorded investment	549	525
Interest income recognized	8	17
Commercial Real Estate [Member] \| Construction [Member]
With an allowance recorded [Abstract]
Recorded investment	102	102
Unpaid principal	102	102
Related allowance	1	15
Average recorded investment	102	102
Interest income recognized	0	0
Total impaired [Abstract]
Recorded investment	102	102
Unpaid principal	102	102
Related allowance	1	15
Average recorded investment	102	102
Interest income recognized	0	0
Consumer Loan [Member] \| Home Equity [Member]
With no related allowance recorded [Abstract]
Recorded investment	224	128
Unpaid principal	224	128
Average recorded investment	186	168
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	321	431
Unpaid principal	321	431
Related allowance	73	73
Average recorded investment	366	418
Interest income recognized	18	24
Total impaired [Abstract]
Recorded investment	545	559
Unpaid principal	545	559
Related allowance	73	73
Average recorded investment	552	586
Interest income recognized	18	24
Commercial Loans [Member]
With no related allowance recorded [Abstract]
Recorded investment	95	145
Unpaid principal	95	145
Average recorded investment	148	137
Interest income recognized	8	1
With an allowance recorded [Abstract]
Recorded investment	3,234	134
Unpaid principal	3,234	134
Related allowance	156	13
Average recorded investment	1,121	147
Interest income recognized	135	9
Total impaired [Abstract]
Recorded investment	3,329	279
Unpaid principal	3,329	279
Related allowance	156	13
Average recorded investment	1,269	284
Interest income recognized	$ 143	$ 10

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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