Loan Quality (Allowance For Loan Losses, By Loan Segment) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				$ 11,075				$ 10,086	$ 11,075	$ 10,086	$ 9,111
Charge-offs									(137)	(3,082)	(571)
Recoveries									184	296	261
Provision	$ 250	$ 250	$ 50	120	$ 450	$ 1,150	$ 1,875	300	670	3,775	1,285
Allowance, Ending Balance	11,792				11,075				11,792	11,075	10,086
Loans evaluated for allowance individually	11,906				14,683				11,906	14,683
Loans evaluated for allowance collectively	931,794				879,190				931,794	879,190
Total Loans	943,700				893,873				943,700	893,873
Allowance established for loan evaluated collectively	11,792				11,075				11,792	11,075
Total Allowance	11,792				11,075				11,792	11,075
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Loans	208,805				218,783				208,805	218,783
Residential Real Estate - Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				224				194	224	194	214
Charge-offs										(41)	(21)
Recoveries											18
Provision										71	(17)
Allowance, Ending Balance	224				224				224	224	194
Loans evaluated for allowance individually	466				480				466	480
Loans evaluated for allowance collectively	9,435				8,495				9,435	8,495
Total Loans	9,901				8,975				9,901	8,975
Allowance established for loan evaluated collectively	224				224				224	224
Total Allowance	224				224				224	224
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				6,109				5,649	6,109	5,649	4,978
Charge-offs									(14)	(2,751)
Recoveries									17	19	14
Provision									414	3,192	657
Allowance, Ending Balance	6,526				6,109				6,526	6,109	5,649
Loans evaluated for allowance individually	10,981				13,523				10,981	13,523
Loans evaluated for allowance collectively	417,447				377,061				417,447	377,061
Total Loans	428,428				390,584				428,428	390,584
Allowance established for loan evaluated collectively	6,526				6,109				6,526	6,109
Total Allowance	6,526				6,109				6,526	6,109
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				1,893				1,519	1,893	1,519	1,515
Charge-offs									(8)	(74)	(270)
Recoveries									117	167	148
Provision									108	281	126
Allowance, Ending Balance	2,110				1,893				2,110	1,893	1,519
Loans evaluated for allowance collectively	291,519				270,826				291,519	270,826
Total Loans	291,519				270,826				291,519	270,826
Allowance established for loan evaluated collectively	2,110				1,893				2,110	1,893
Total Allowance	2,110				1,893				2,110	1,893
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				100				102	100	102	127
Charge-offs									(102)	(167)	(198)
Recoveries									37	75	74
Provision									70	90	99
Allowance, Ending Balance	105				100				105	100	102
Loans evaluated for allowance collectively	5,047				4,705				5,047	4,705
Total Loans	5,047				4,705				5,047	4,705
Allowance established for loan evaluated collectively	105				100				105	100
Total Allowance	105				100				105	100
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				1,321				1,325	1,321	1,325	1,012
Provision									116	(4)	313
Allowance, Ending Balance	1,437				1,321				1,437	1,321	1,325
Allowance established for loan evaluated collectively	1,437				1,321				1,437	1,321
Total Allowance	1,437				1,321				1,437	1,321
First Liens [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				1,105				989	1,105	989	994
Charge-offs									(13)	(49)	(43)
Recoveries									2	35	7
Provision									(34)	130	31
Allowance, Ending Balance	1,060				1,105				1,060	1,105	989
Loans evaluated for allowance individually	459				628				459	628
Loans evaluated for allowance collectively	157,975				167,942				157,975	167,942
Total Loans	158,434				168,570				158,434	168,570
Allowance established for loan evaluated collectively	1,060				1,105				1,060	1,105
Total Allowance	1,060				1,105				1,060	1,105
Junior Liens & Lines Of Credit [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance, Beginning Balance				$ 323				$ 308	323	308	271
Charge-offs											(39)
Recoveries									11
Provision									(4)	15	76
Allowance, Ending Balance	330				323				330	323	$ 308
Loans evaluated for allowance individually					52					52
Loans evaluated for allowance collectively	50,371				50,161				50,371	50,161
Total Loans	50,371				50,213				50,371	50,213
Allowance established for loan evaluated collectively	330				323				330	323
Total Allowance	$ 330				$ 323				$ 330	$ 323