Loans and Allowance for Loan Losses, Activity and Allocation of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Jun. 30, 2022
Allowance for Loan Losses [Abstract]
Threshold principal amount of nonaccrual loans evaluated individually for impairment	$ 250		$ 250
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	22,147	$ 20,493	22,761	$ 19,668
Charge-offs	144	117	315	318
Recoveries	42	28	98	66
Provision	244	1,280	(255)	2,268
Balance, end of period	22,289	21,684	22,289	21,684
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	2,617		2,617		$ 2,347
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	19,672		19,672		20,414
Loans receivable, ending balance, impairment analysis individually evaluated	10,242		10,242		10,771
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 1,379,813		$ 1,379,813		1,241,216
Smaller Business Loans [Member] \| Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days		90 days
Residential Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 2,471	1,997	$ 2,373	2,012
Charge-offs	0	0	0	0
Recoveries	2	7	5	7
Provision	19	(23)	114	(38)
Balance, end of period	2,492	1,981	2,492	1,981
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	587		587		588
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,905		1,905		1,785
Loans receivable, ending balance, impairment analysis individually evaluated	3,213		3,213		2,943
Loans receivable, ending balance, impairment analysis collectively evaluated	368,433		368,433		357,881
Residential Real Estate [Member] \| Construction and Land [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	177	120	141	106
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	16	(5)	52	9
Balance, end of period	193	115	193	115
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	193		193		141
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	20,334		20,334		15,298
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	159	100	119	186
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	8	(24)	48	(110)
Balance, end of period	167	76	167	76
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	167		167		119
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	67,733		67,733		63,822
Commercial Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	15,392	14,298	16,221	13,049
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	58	1,318	(771)	2,567
Balance, end of period	15,450	15,616	15,450	15,616
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	1,090		1,090		1,118
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	14,360		14,360		15,103
Loans receivable, ending balance, impairment analysis individually evaluated	4,471		4,471		3,765
Loans receivable, ending balance, impairment analysis collectively evaluated	701,178		701,178		591,870
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	1,044	1,198	1,114	1,535
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	56	52	(14)	(285)
Balance, end of period	1,100	1,250	1,100	1,250
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	1		1		1
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,099		1,099		1,113
Loans receivable, ending balance, impairment analysis individually evaluated	102		102		102
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 87,165		$ 87,165		83,646
Consumer Loan [Member] \| Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days		90 days
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 44	140	$ 89	165
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(6)	(51)	(51)	(76)
Balance, end of period	38	89	38	89
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		44
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	38		38		45
Loans receivable, ending balance, impairment analysis individually evaluated	128		128		448
Loans receivable, ending balance, impairment analysis collectively evaluated	20,541		20,541		17,429
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	274	290	349	267
Charge-offs	137	107	304	211
Recoveries	29	20	75	57
Provision	118	77	164	167
Balance, end of period	284	280	284	280
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	284		284		349
Loans receivable, ending balance, impairment analysis individually evaluated	4		4		5
Loans receivable, ending balance, impairment analysis collectively evaluated	4,584		$ 4,584		4,507
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	2,586	2,350	$ 2,355	2,348
Charge-offs	7	10	11	107
Recoveries	11	1	18	2
Provision	(25)	(64)	203	34
Balance, end of period	2,565	$ 2,277	2,565	$ 2,277
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	939		939		596
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,626		1,626		1,759
Loans receivable, ending balance, impairment analysis individually evaluated	2,324		2,324		3,508
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 109,845		$ 109,845		$ 106,763

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

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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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The balance of financing receivables that were collectively 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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