Loan Quality and Allowance for Loan Losses (Allowance For Loan Losses, By Loan Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	$ 11,989	$ 11,278	$ 11,792	$ 11,075
Charge-offs	(8,765)	(36)	(8,791)	(72)
Recoveries	129	15	152	134
Provision	9,129	50	9,329	170
Allowance, Ending Balance	12,482	11,307	12,482	11,307
Loans evaluated for allowance individually	14,799		14,799		$ 11,906
Loans evaluated for allowance collectively	952,497		952,497		931,794
Total Loans	967,296		967,296		943,700
Allowance established for loans evaluated individually	225		225
Allowance established for loan evaluated collectively	12,257		12,257		11,792
Total Allowance	12,482		12,482		11,792
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Loans	200,875		200,875		208,805
Residential Real Estate - Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	260	274	224	224
Provision	22	7	58	57
Allowance, Ending Balance	282	281	282	281
Loans evaluated for allowance individually	462		462		466
Loans evaluated for allowance collectively	12,015		12,015		9,435
Total Loans	12,477		12,477		9,901
Allowance established for loan evaluated collectively	282		282		224
Total Allowance	282		282		224
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	6,698	6,126	6,526	6,109
Charge-offs		(5)		(5)
Recoveries	16		16
Provision	314	(69)	486	(52)
Allowance, Ending Balance	7,028	6,052	7,028	6,052
Loans evaluated for allowance individually	10,754		10,754		10,981
Loans evaluated for allowance collectively	454,146		454,146		417,447
Total Loans	464,900		464,900		428,428
Allowance established for loan evaluated collectively	7,028		7,028		6,526
Total Allowance	7,028		7,028		6,526
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	2,073	1,984	2,110	1,893
Charge-offs	(8,736)	(2)	(8,736)	(2)
Recoveries	108	4	116	106
Provision	8,788	37	8,743	26
Allowance, Ending Balance	2,233	2,023	2,233	2,023
Loans evaluated for allowance individually	3,133		3,133
Loans evaluated for allowance collectively	280,927		280,927		291,519
Total Loans	284,060		284,060		291,519
Allowance established for loans evaluated individually	225		225
Allowance established for loan evaluated collectively	2,008		2,008		2,110
Total Allowance	2,233		2,233		2,110
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	104	99	105	100
Charge-offs	(29)	(24)	(55)	(52)
Recoveries	5	10	19	26
Provision	27	15	38	26
Allowance, Ending Balance	107	100	107	100
Loans evaluated for allowance collectively	4,984		4,984		5,047
Total Loans	4,984		4,984		5,047
Allowance established for loan evaluated collectively	107		107		105
Total Allowance	107		107		105
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	1,491	1,374	1,437	1,321
Provision	1	80	55	133
Allowance, Ending Balance	1,492	1,454	1,492	1,454
Allowance established for loan evaluated collectively	1,492		1,492		1,437
Total Allowance	1,492		1,492		1,437
First Liens [Member] \| Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	1,043	1,100	1,060	1,105
Charge-offs		(5)		(13)
Recoveries			1	1
Provision	(21)	(20)	(39)	(18)
Allowance, Ending Balance	1,022	1,075	1,022	1,075
Loans evaluated for allowance individually	450		450		459
Loans evaluated for allowance collectively	151,896		151,896		157,975
Total Loans	152,346		152,346		158,434
Allowance established for loan evaluated collectively	1,022		1,022		1,060
Total Allowance	1,022		1,022		1,060
Junior Liens & Lines Of Credit [Member] \| Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance	320	321	330	323
Recoveries		1		1
Provision	(2)		(12)	(2)
Allowance, Ending Balance	318	$ 322	318	$ 322
Loans evaluated for allowance collectively	48,529		48,529		50,371
Total Loans	48,529		48,529		50,371
Allowance established for loan evaluated collectively	318		318		330
Total Allowance	$ 318		$ 318		$ 330

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

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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The balance of financing receivables that were collectively evaluated for impairment.

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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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