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, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2017
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 11,098	$ 9,976	$ 11,022	$ 9,485
Charge-offs	116	159	405	231
Recoveries	18	18	36	38
Provision	352	586	699	1,129
Balance, end of period	11,352	10,421	11,352	10,421
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	533		533		$ 436
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	10,819		10,819		10,586
Loans receivable, ending balance, impairment analysis individually evaluated	4,073		4,073		3,252
Loans receivable, ending balance, impairment analysis collectively evaluated	670,362		670,362		631,079
Residential Real Estate [Member] \| Residential Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	2,076	2,242	2,289	2,396
Charge-offs	27	90	71	90
Recoveries	0	0	0	0
Provision	50	82	(119)	(72)
Balance, end of period	2,099	2,234	2,099	2,234
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	348		348		278
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,751		1,751		2,011
Loans receivable, ending balance, impairment analysis individually evaluated	1,819		1,819		1,455
Loans receivable, ending balance, impairment analysis collectively evaluated	250,196		250,196		243,876
Residential Real Estate [Member] \| Construction and Land [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	93	63	89	75
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(7)	0	(3)	(12)
Balance, end of period	86	63	86	63
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	86		86		89
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	7,391		7,391		7,160
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	76	18	43	22
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	19	0	52	(4)
Balance, end of period	95	18	95	18
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	95		95		43
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	13,707		13,707		9,199
Commercial Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	5,759	4,981	5,589	4,541
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	145	384	315	824
Balance, end of period	5,904	5,365	5,904	5,365
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	101		101		135
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	5,803		5,803		5,454
Loans receivable, ending balance, impairment analysis individually evaluated	1,214		1,214		1,249
Loans receivable, ending balance, impairment analysis collectively evaluated	271,039		271,039		256,715
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	750	628	687	502
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(147)	(25)	(84)	101
Balance, end of period	603	603	603	603
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	22		22		23
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	581		581		664
Loans receivable, ending balance, impairment analysis individually evaluated	176		176		176
Loans receivable, ending balance, impairment analysis collectively evaluated	24,725		24,725		28,254
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	315	251	234	309
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(3)	6	78	(52)
Balance, end of period	312	257	312	257
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	62		62		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	250		250		234
Loans receivable, ending balance, impairment analysis individually evaluated	505		505		186
Loans receivable, ending balance, impairment analysis collectively evaluated	20,585		20,585		20,890
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	203	168	231	228
Charge-offs	89	69	177	141
Recoveries	18	18	36	35
Provision	120	107	162	102
Balance, end of period	252	224	252	224
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	252		252		231
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	4,925		4,925		4,790
Commercial Loans [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	1,748	1,492	1,680	1,412
Charge-offs	0	0	157	0
Recoveries	0	0	0	3
Provision	253	21	478	98
Balance, end of period	2,001	1,513	2,001	1,513
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	2,001		2,001		1,680
Loans receivable, ending balance, impairment analysis individually evaluated	359		359		186
Loans receivable, ending balance, impairment analysis collectively evaluated	77,794		77,794		60,195
Unallocated [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	78	133	180	0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(78)	11	(180)	144
Balance, end of period	0	$ 144	0	$ 144
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	0		0		180
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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- Definition

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

+ References

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- Definition

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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- 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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