Loans and Allowance for Loan Losses, Activity and Allocation of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Jun. 30, 2018
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 12,673	$ 11,352	$ 12,024	$ 11,022
Charge-offs	220	104	505	509
Recoveries	43	29	269	65
Provision	350	345	1,058	1,044
Balance, end of period	12,846	11,622	12,846	11,622
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	392		392		$ 482
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	12,454		12,454		11,542
Loans receivable, ending balance, impairment analysis individually evaluated	3,878		3,878		4,148
Loans receivable, ending balance, impairment analysis collectively evaluated	771,474		771,474		711,493
Residential Real Estate [Member] \| Residential Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	2,070	2,099	2,116	2,289
Charge-offs	0	25	96	96
Recoveries	0	0	13	0
Provision	14	5	51	(114)
Balance, end of period	2,084	2,079	2,084	2,079
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	292		292		332
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,792		1,792		1,784
Loans receivable, ending balance, impairment analysis individually evaluated	2,112		2,112		1,944
Loans receivable, ending balance, impairment analysis collectively evaluated	266,180		266,180		253,904
Residential Real Estate [Member] \| Construction and Land [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	93	86	114	89
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(13)	8	(34)	5
Balance, end of period	80	94	80	94
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	80		80		114
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	6,780		6,780		9,951
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	180	95	162	43
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(12)	67	6	119
Balance, end of period	168	162	168	162
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	168		168		162
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	22,131		22,131		14,961
Commercial Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	6,182	5,904	5,979	5,589
Charge-offs	74	0	74	0
Recoveries	0	0	0	0
Provision	238	52	441	367
Balance, end of period	6,346	5,956	6,346	5,956
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		60
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	6,346		6,346		5,919
Loans receivable, ending balance, impairment analysis individually evaluated	730		730		1,178
Loans receivable, ending balance, impairment analysis collectively evaluated	308,505		308,505		282,757
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	876	603	950	687
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	117	136	43	52
Balance, end of period	993	739	993	739
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		29
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	993		993		921
Loans receivable, ending balance, impairment analysis individually evaluated	102		102		176
Loans receivable, ending balance, impairment analysis collectively evaluated	41,384		41,384		39,190
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	322	312	317	234
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(18)	0	(13)	78
Balance, end of period	304	312	304	312
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	59		59		61
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	245		245		256
Loans receivable, ending balance, impairment analysis individually evaluated	658		658		503
Loans receivable, ending balance, impairment analysis collectively evaluated	21,550		21,550		21,416
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	290	252	224	231
Charge-offs	95	79	284	256
Recoveries	43	29	103	65
Provision	(28)	(14)	167	148
Balance, end of period	210	188	210	188
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	210		210		224
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	5,213		5,213		5,017
Commercial Loans [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	2,381	2,001	2,128	1,680
Charge-offs	51	0	51	157
Recoveries	0	0	153	0
Provision	(49)	(26)	51	452
Balance, end of period	2,281	1,975	2,281	1,975
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	41		41		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	2,240		2,240		2,128
Loans receivable, ending balance, impairment analysis individually evaluated	276		276		347
Loans receivable, ending balance, impairment analysis collectively evaluated	99,731		99,731		84,297
Unallocated [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	279	0	34	180
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	101	117	346	(63)
Balance, end of period	380	$ 117	380	$ 117
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	380		380		34
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 0		$ 0		$ 0

Amount of recoveries of receivables doubtful of collection that were previously charged off.

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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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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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