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, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Allowance for Loan Losses [Abstract]
Increase in provision for credit losses to reserve for losses resulting from COVID-19 pandemic	$ 1,300	$ 690	$ 2,500	$ 1,200
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	17,596	13,444	16,391	13,200
Charge-offs	611	192	672	553
Recoveries	23	42	46	96
Provision	1,262	690	2,505	1,241
Balance, end of period	18,270	13,984	18,270	13,984
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	177		177		$ 228
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	18,093		18,093		16,163
Loans receivable, ending balance, impairment analysis individually evaluated	2,157		2,157		3,270
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 1,049,010		$ 1,049,010		1,009,390
Smaller Commercial 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] \| Residential Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 1,463	1,512	$ 2,091	2,026
Charge-offs	26	48	26	101
Recoveries	4	10	7	10
Provision	557	(4)	(74)	(465)
Balance, end of period	1,998	1,470	1,998	1,470
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	82		82		127
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,916		1,916		1,964
Loans receivable, ending balance, impairment analysis individually evaluated	1,054		1,054		1,863
Loans receivable, ending balance, impairment analysis collectively evaluated	298,425		298,425		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	118	99	141	87
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(28)	(6)	(51)	6
Balance, end of period	90	93	90	93
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	90		90		141
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	7,494		7,494		11,847
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	180	205	176	180
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	96	(58)	100	(33)
Balance, end of period	276	147	276	147
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	276		276		176
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		123
Loans receivable, ending balance, impairment analysis collectively evaluated	28,000		28,000		24,981
Commercial Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	9,384	7,159	8,634	7,110
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	823	351	1,573	400
Balance, end of period	10,207	7,510	10,207	7,510
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	10,207		10,207		8,634
Loans receivable, ending balance, impairment analysis individually evaluated	316		316		344
Loans receivable, ending balance, impairment analysis collectively evaluated	447,806		447,806		381,071
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	1,961	1,291	2,053	872
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(114)	176	(206)	595
Balance, end of period	1,847	1,467	1,847	1,467
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	20		20		15
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,827		1,827		2,038
Loans receivable, ending balance, impairment analysis individually evaluated	102		102		102
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 72,098		$ 72,098		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		90 days
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 272	307	$ 295	314
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(7)	(37)	(30)	(44)
Balance, end of period	265	270	265	270
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	73		73		73
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	192		192		222
Loans receivable, ending balance, impairment analysis individually evaluated	552		552		559
Loans receivable, ending balance, impairment analysis collectively evaluated	19,370		19,370		21,547
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	350	319	197	250
Charge-offs	85	139	146	248
Recoveries	19	26	39	50
Provision	(28)	160	166	314
Balance, end of period	256	366	256	366
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	256		256		197
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	4,851		$ 4,851		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	3,868	2,552	$ 2,804	2,361
Charge-offs	500	5	500	204
Recoveries	0	6	0	36
Provision	(37)	108	1,027	468
Balance, end of period	3,331	$ 2,661	3,331	$ 2,661
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	2		2		13
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	3,329		3,329		2,791
Loans receivable, ending balance, impairment analysis individually evaluated	133		133		279
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 170,966		$ 170,966		$ 212,840

Amount of increase in provision for credit losses to reserve for losses resulting from COVID-19 pandemic.

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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 increase in allowance for credit loss on accounts receivable, from recovery.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of accounts receivable charged against the allowance.

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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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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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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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