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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Loans and Allowance for Loan Losses, Major Loan Segments and Classes (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 674,435		$ 634,331
Allowance for loan losses	(11,352)	$ (11,098)	(11,022)	$ (10,421)	$ (9,976)	$ (9,485)
Deferred fees and costs	790		878
Net loans receivable	663,873		624,187
Residential Real Estate [Member] \| Residential Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	252,015		245,331
Allowance for loan losses	(2,099)	(2,076)	(2,289)	(2,234)	(2,242)	(2,396)
Residential Real Estate [Member] \| Construction and Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	7,391		7,160
Allowance for loan losses	(86)	(93)	(89)	(63)	(63)	(75)
Residential Real Estate [Member] \| Multi-family [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	13,707		9,199
Allowance for loan losses	(95)	(76)	(43)	(18)	(18)	(22)
Commercial Real Estate [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	272,253		257,964
Allowance for loan losses	(5,904)	(5,759)	(5,589)	(5,365)	(4,981)	(4,541)
Commercial Real Estate [Member] \| Construction [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	24,901		28,430
Allowance for loan losses	(603)	(750)	(687)	(603)	(628)	(502)
Consumer Loan [Member] \| Home Equity [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	21,090		21,076
Allowance for loan losses	(312)	(315)	(234)	(257)	(251)	(309)
Consumer Loan [Member] \| Consumer Installment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	4,925		4,790
Allowance for loan losses	(252)	(203)	(231)	(224)	(168)	(228)
Commercial Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	78,153		60,381
Allowance for loan losses	$ (2,001)	$ (1,748)	$ (1,680)	$ (1,513)	$ (1,492)	$ (1,412)