Loans, Activity and Allocation of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 9,485	$ 8,142
Charge-offs	465	427
Recoveries	91	97
Provision	1,911	1,673
Balance, end of period	11,022	9,485
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	436	330
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	10,586	9,155
Loans receivable, ending balance, impairment analysis individually evaluated	3,252	3,242
Loans receivable, ending balance, impairment analysis collectively evaluated	631,079	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	2,396	2,454
Charge-offs	90	0
Recoveries	0	0
Provision	(17)	(58)
Balance, end of period	2,289	2,396
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	278	267
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	2,011	2,129
Loans receivable, ending balance, impairment analysis individually evaluated	1,455	1,723
Loans receivable, ending balance, impairment analysis collectively evaluated	243,876	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	75	50
Charge-offs	0	0
Recoveries	0	0
Provision	14	25
Balance, end of period	89	75
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	89	75
Loans receivable, ending balance, impairment analysis individually evaluated	0	0
Loans receivable, ending balance, impairment analysis collectively evaluated	7,160	5,575
Residential Real Estate [Member] \| Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	22	40
Charge-offs	0	0
Recoveries	0	0
Provision	21	(18)
Balance, end of period	43	22
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	43	22
Loans receivable, ending balance, impairment analysis individually evaluated	0	0
Loans receivable, ending balance, impairment analysis collectively evaluated	9,199	3,918
Commercial Real Estate [Member] \| Real Estate Mortgage [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	4,541	3,699
Charge-offs	39	162
Recoveries	0	17
Provision	1,087	987
Balance, end of period	5,589	4,541
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	135	61
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	5,454	4,480
Loans receivable, ending balance, impairment analysis individually evaluated	1,249	1,429
Loans receivable, ending balance, impairment analysis collectively evaluated	256,715	191,249
Commercial Real Estate [Member] \| Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	502	233
Charge-offs	0	0
Recoveries	0	0
Provision	185	269
Balance, end of period	687	502
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	23	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	664	502
Loans receivable, ending balance, impairment analysis individually evaluated	176	0
Loans receivable, ending balance, impairment analysis collectively evaluated	28,254	20,159
Consumer Loan [Member] \| Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	309	314
Charge-offs	0	0
Recoveries	0	0
Provision	(75)	(5)
Balance, end of period	234	309
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	234	309
Loans receivable, ending balance, impairment analysis individually evaluated	186	5
Loans receivable, ending balance, impairment analysis collectively evaluated	20,890	20,888
Consumer Loan [Member] \| Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	228	223
Charge-offs	270	245
Recoveries	88	78
Provision	185	172
Balance, end of period	231	228
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	231	228
Loans receivable, ending balance, impairment analysis individually evaluated	0	0
Loans receivable, ending balance, impairment analysis collectively evaluated	4,790	4,350
Commercial Loans [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	1,412	1,129
Charge-offs	66	20
Recoveries	3	2
Provision	331	301
Balance, end of period	1,680	1,412
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0	2
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,680	1,410
Loans receivable, ending balance, impairment analysis individually evaluated	186	85
Loans receivable, ending balance, impairment analysis collectively evaluated	60,195	48,640
Unallocated [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	0
Charge-offs	0
Recoveries	0
Provision	180
Balance, end of period	180	$ 0
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	180
Loans receivable, ending balance, impairment analysis individually evaluated	0
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 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.

+ 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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