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	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 689,370		$ 634,331
Allowance for loan losses	(11,622)	$ (11,352)	(11,022)	$ (10,721)	$ (10,421)	$ (9,485)
Deferred fees and costs	747		878
Net loans receivable	678,495		624,187
Residential Real Estate [Member] \| Residential Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	253,345		245,331
Allowance for loan losses	(2,079)	(2,099)	(2,289)	(2,263)	(2,234)	(2,396)
Residential Real Estate [Member] \| Construction and Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	8,153		7,160
Allowance for loan losses	(94)	(86)	(89)	(78)	(63)	(75)
Residential Real Estate [Member] \| Multi-family [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	14,201		9,199
Allowance for loan losses	(162)	(95)	(43)	(34)	(18)	(22)
Commercial Real Estate [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	279,476		257,964
Allowance for loan losses	(5,956)	(5,904)	(5,589)	(5,506)	(5,365)	(4,541)
Commercial Real Estate [Member] \| Construction [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	30,495		28,430
Allowance for loan losses	(739)	(603)	(687)	(648)	(603)	(502)
Consumer Loan [Member] \| Home Equity [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	21,290		21,076
Allowance for loan losses	(312)	(312)	(234)	(227)	(257)	(309)
Consumer Loan [Member] \| Consumer Installment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	4,863		4,790
Allowance for loan losses	(188)	(252)	(231)	(164)	(224)	(228)
Commercial Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	77,547		60,381
Allowance for loan losses	$ (1,975)	$ (2,001)	$ (1,680)	$ (1,571)	$ (1,513)	$ (1,412)