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, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2018
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 12,308	$ 11,098	$ 12,024	$ 11,022
Charge-offs	164	116	284	405
Recoveries	175	18	225	36
Provision	354	352	708	699
Balance, end of period	12,673	11,352	12,673	11,352
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	356		356		$ 482
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	12,317		12,317		11,542
Loans receivable, ending balance, impairment analysis individually evaluated	4,110		4,110		4,148
Loans receivable, ending balance, impairment analysis collectively evaluated	758,123		758,123		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	2,108	2,076	2,116	2,289
Charge-offs	75	27	96	71
Recoveries	0	0	13	0
Provision	37	50	37	(119)
Balance, end of period	2,070	2,099	2,070	2,099
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	221		221		332
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,849		1,849		1,784
Loans receivable, ending balance, impairment analysis individually evaluated	1,850		1,850		1,944
Loans receivable, ending balance, impairment analysis collectively evaluated	266,613		266,613		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	116	93	114	89
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(23)	(7)	(21)	(3)
Balance, end of period	93	86	93	86
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	93		93		114
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	7,875		7,875		9,951
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	171	76	162	43
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	9	19	18	52
Balance, end of period	180	95	180	95
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	180		180		162
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	22,626		22,626		14,961
Commercial Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	6,023	5,759	5,979	5,589
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	159	145	203	315
Balance, end of period	6,182	5,904	6,182	5,904
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	6,182		6,182		5,919
Loans receivable, ending balance, impairment analysis individually evaluated	1,141		1,141		1,178
Loans receivable, ending balance, impairment analysis collectively evaluated	299,584		299,584		282,757
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	957	750	950	687
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(81)	(147)	(74)	(84)
Balance, end of period	876	603	876	603
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	34		34		29
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	842		842		921
Loans receivable, ending balance, impairment analysis individually evaluated	176		176		176
Loans receivable, ending balance, impairment analysis collectively evaluated	35,079		35,079		39,190
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	317	315	317	234
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	5	(3)	5	78
Balance, end of period	322	312	322	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	263		263		256
Loans receivable, ending balance, impairment analysis individually evaluated	660		660		503
Loans receivable, ending balance, impairment analysis collectively evaluated	21,753		21,753		21,416
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	229	203	224	231
Charge-offs	89	89	188	177
Recoveries	22	18	59	36
Provision	128	120	195	162
Balance, end of period	290	252	290	252
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	290		290		224
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	5,344		5,344		5,017
Commercial Loans [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	2,133	1,748	2,128	1,680
Charge-offs	0	0	0	157
Recoveries	153	0	153	0
Provision	95	253	100	478
Balance, end of period	2,381	2,001	2,381	2,001
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	42		42		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	2,339		2,339		2,128
Loans receivable, ending balance, impairment analysis individually evaluated	283		283		347
Loans receivable, ending balance, impairment analysis collectively evaluated	99,249		99,249		84,297
Unallocated [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	254	78	34	180
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	25	(78)	245	(180)
Balance, end of period	279	$ 0	279	$ 0
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	279		279		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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