Loans Receivable and Allowance for Loan Losses (Composition of the Loan Portfolio) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 864,314	$ 850,302
Deferred fees, net	(116)	(120)
Total loans receivable	864,198	850,182
Allowance for loan losses	(8,349)	(8,452)	$ (8,099)	$ (7,634)
Net loans receivable	$ 855,849	$ 841,730
Percent of Loans	100.00%	100.00%
Residential Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 231,954	$ 235,523
Allowance for loan losses	$ (1,455)	$ (1,328)	(1,525)	(1,272)
Percent of Loans	26.80%	27.70%
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 373,276	$ 374,790
Allowance for loan losses	$ (4,947)	$ (5,455)	(5,129)	(5,265)
Percent of Loans	43.20%	44.10%
Construction Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 18,604	$ 17,445
Allowance for loan losses	$ (108)	$ (93)	(120)	(90)
Percent of Loans	2.20%	2.00%
Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 118,535	$ 110,542
Allowance for loan losses	$ (811)	$ (712)	(638)	(463)
Percent of Loans	13.70%	13.00%
Consumer Loans To Individuals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 121,945	$ 112,002
Allowance for loan losses	$ (1,028)	$ (864)	$ (687)	$ (544)
Percent of Loans	14.10%	13.20%

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A valuation allowance for financing receivables that are expected to be uncollectible.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts 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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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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