Loans, Activity and Allocation of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Allowance for Loan Losses [Abstract]
Threshold principal amount of nonaccrual loans evaluated individually for impairment	$ 100
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	16,391	$ 13,200
Charge-offs	835	896
Recoveries	138	182
Provision	3,974	3,905
Balance, end of period	19,668	16,391
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	391	228
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	19,277	16,163
Loans receivable, ending balance, impairment analysis individually evaluated	6,295	3,270
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 1,102,113	1,009,390
Smaller Business Loans [Member] \| Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days
Residential Real Estate [Member] \| Residential Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 2,091	2,026
Charge-offs	26	102
Recoveries	13	16
Provision	(66)	151
Balance, end of period	2,012	2,091
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	103	127
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,909	1,964
Loans receivable, ending balance, impairment analysis individually evaluated	1,093	1,863
Loans receivable, ending balance, impairment analysis collectively evaluated	324,074	277,469
Residential Real Estate [Member] \| Construction and Land [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	141	87
Charge-offs	0	0
Recoveries	0	0
Provision	(35)	54
Balance, end of period	106	141
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	106	141
Loans receivable, ending balance, impairment analysis individually evaluated	0	0
Loans receivable, ending balance, impairment analysis collectively evaluated	10,185	11,847
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	176	180
Charge-offs	0	0
Recoveries	0	0
Provision	10	(4)
Balance, end of period	186	176
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	186	176
Loans receivable, ending balance, impairment analysis individually evaluated	0	123
Loans receivable, ending balance, impairment analysis collectively evaluated	41,951	24,981
Commercial Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	8,634	7,110
Charge-offs	0	0
Recoveries	0	0
Provision	4,415	1,524
Balance, end of period	13,049	8,634
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	58	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	12,991	8,634
Loans receivable, ending balance, impairment analysis individually evaluated	1,226	344
Loans receivable, ending balance, impairment analysis collectively evaluated	471,661	381,071
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	2,053	872
Charge-offs	0	0
Recoveries	0	0
Provision	(518)	1,181
Balance, end of period	1,535	2,053
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	1	15
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,534	2,038
Loans receivable, ending balance, impairment analysis individually evaluated	102	102
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 62,661	74,818
Consumer Loan [Member] \| Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 295	314
Charge-offs	0	0
Recoveries	0	0
Provision	(130)	(19)
Balance, end of period	165	295
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	73	73
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	92	222
Loans receivable, ending balance, impairment analysis individually evaluated	545	559
Loans receivable, ending balance, impairment analysis collectively evaluated	17,740	21,547
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	197	250
Charge-offs	309	459
Recoveries	124	130
Provision	255	276
Balance, end of period	267	197
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	267	197
Loans receivable, ending balance, impairment analysis individually evaluated	0	0
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 4,942	4,817
Consumer Loan [Member] \| Consumer Installment [Member] \| Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off overdrawn deposit accounts against allowance for loan losses	60 days
Commercial Loans [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 2,804	2,361
Charge-offs	500	335
Recoveries	1	36
Provision	43	742
Balance, end of period	2,348	2,804
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	156	13
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	2,192	2,791
Loans receivable, ending balance, impairment analysis individually evaluated	3,329	279
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 168,899	$ 212,840

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

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- Definition

Threshold period for overdrawn financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Threshold period for when financing receivable is considered past due to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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