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, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 9,976	$ 8,466	$ 9,485	$ 8,142
Charge-offs	159	213	231	305
Recoveries	18	15	38	57
Provision	586	343	1,129	717
Balance, end of period	10,421	8,611	10,421	8,611
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	467		467		$ 330
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	9,954		9,954		9,155
Loans receivable, ending balance, impairment analysis individually evaluated	3,653		3,653		3,242
Loans receivable, ending balance, impairment analysis collectively evaluated	597,229		597,229		528,048
Residential Real Estate [Member] \| Residential Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	2,242	2,386	2,396	2,454
Charge-offs	90	0	90	0
Recoveries	0	0	0	0
Provision	82	6	(72)	(62)
Balance, end of period	2,234	2,392	2,234	2,392
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	244		244		267
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,990		1,990		2,129
Loans receivable, ending balance, impairment analysis individually evaluated	1,501		1,501		1,723
Loans receivable, ending balance, impairment analysis collectively evaluated	236,930		236,930		233,269
Residential Real Estate [Member] \| Construction and Land [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	63	62	75	50
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	0	8	(12)	20
Balance, end of period	63	70	63	70
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	63		63		75
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	4,980		4,980		5,575
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	18	25	22	40
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	0	0	(4)	(15)
Balance, end of period	18	25	18	25
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	18		18		22
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	3,904		3,904		3,918
Commercial Real Estate [Member] \| Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	4,981	3,814	4,541	3,699
Charge-offs	0	148	0	162
Recoveries	0	0	0	17
Provision	384	354	824	466
Balance, end of period	5,365	4,020	5,365	4,020
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	221		221		61
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	5,144		5,144		4,480
Loans receivable, ending balance, impairment analysis individually evaluated	1,876		1,876		1,429
Loans receivable, ending balance, impairment analysis collectively evaluated	244,430		244,430		191,249
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	628	162	502	233
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(25)	169	101	98
Balance, end of period	603	331	603	331
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	603		603		502
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	25,651		25,651		20,159
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	251	319	309	314
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	6	(14)	(52)	(9)
Balance, end of period	257	305	257	305
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	257		257		309
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		5
Loans receivable, ending balance, impairment analysis collectively evaluated	20,660		20,660		20,888
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	168	240	228	223
Charge-offs	69	65	141	143
Recoveries	18	15	35	40
Provision	107	(2)	102	68
Balance, end of period	224	188	224	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	224		224		228
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	4,714		4,714		4,350
Commercial Loans [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	1,492	1,252	1,412	1,129
Charge-offs	0	0	0	0
Recoveries	0	0	3	0
Provision	21	20	98	143
Balance, end of period	1,513	1,272	1,513	1,272
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	2		2		2
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,511		1,511		1,410
Loans receivable, ending balance, impairment analysis individually evaluated	276		276		85
Loans receivable, ending balance, impairment analysis collectively evaluated	55,960		55,960		48,640
Unallocated [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	133	206	0	0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	11	(198)	144	8
Balance, end of period	144	$ 8	144	$ 8
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	144		144		0
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.

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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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