Allowance for Credit Losses (Allowance For Credit Losses And Recorded Investments In Loans Receivables) (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
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				$ 5,373				$ 4,935	$ 5,373	$ 4,935
Charge-offs									(1,325)	(311)
Recoveries									135	19
Provisions	$ 375	$ 375	$ 585	325	$ 100	$ 100	$ 200	330	1,660	730
Ending balance	5,843				5,373				5,843	5,373
Ending balance: individually evaluated for impairment	157				334				157	334
Ending balance: collectively evaluated for impairment	5,686				5,039				5,686	5,039
Ending balance: Loans receivables	845,897				817,529				845,897	817,529
Ending Balance: individually evaluated for impairment	8,187				6,919				8,187	6,919
Ending Balance: collectively evaluated for impairment	836,767				808,925				836,767	808,925
Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Ending balance: Loans receivables	943				1,685				943	1,685
Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				349				216	349	216
Charge-offs									(85)	(206)
Recoveries									16	13
Provisions									(59)	326
Ending balance	221				349				221	349
Ending balance: individually evaluated for impairment	3				143				3	143
Ending balance: collectively evaluated for impairment	218				206				218	206
Ending balance: Loans receivables	93,959				87,581				93,959	87,581
Ending Balance: individually evaluated for impairment	1,908				1,760				1,908	1,760
Ending Balance: collectively evaluated for impairment	92,044				85,810				92,044	85,810
Residential Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Ending balance: Loans receivables	7				11				7	11
Commercial Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				2,531				2,375	2,531	2,375
Charge-offs									(519)	(39)
Recoveries									51
Provisions									793	195
Ending balance	2,856				2,531				2,856	2,531
Ending balance: individually evaluated for impairment	19								19
Ending balance: collectively evaluated for impairment	2,837				2,531				2,837	2,531
Ending balance: Loans receivables	484,868				465,486				484,868	465,486
Ending Balance: individually evaluated for impairment	2,828				2,919				2,828	2,919
Ending Balance: collectively evaluated for impairment	481,104				460,893				481,104	460,893
Commercial Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Ending balance: Loans receivables	936				1,674				936	1,674
Commercial Term [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				709				989	709	989
Charge-offs									(683)	(45)
Recoveries									23	1
Provisions									796	(236)
Ending balance	845				709				845	709
Ending balance: individually evaluated for impairment	123				97				123	97
Ending balance: collectively evaluated for impairment	722				612				722	612
Ending balance: Loans receivables	129,535				123,175				129,535	123,175
Ending Balance: individually evaluated for impairment	2,080				198				2,080	198
Ending Balance: collectively evaluated for impairment	127,455				122,977				127,455	122,977
Commercial Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				969				569	969	569
Recoveries									42	1
Provisions									117	399
Ending balance	1,128				969				1,128	969
Ending balance: individually evaluated for impairment					89					89
Ending balance: collectively evaluated for impairment	1,128				880				1,128	880
Ending balance: Loans receivables	75,014				72,755				75,014	72,755
Ending Balance: individually evaluated for impairment	514				1,242				514	1,242
Ending Balance: collectively evaluated for impairment	74,500				71,513				74,500	71,513
Leases Financing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Recoveries									1	3
Provisions									(1)	(3)
Consumer: Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				196				195	196	195
Provisions									(13)	1
Ending balance	183				196				183	196
Ending balance: collectively evaluated for impairment	183				196				183	196
Ending balance: Loans receivables	56,844				62,560				56,844	62,560
Ending Balance: individually evaluated for impairment	612				544				612	544
Ending Balance: collectively evaluated for impairment	56,232				62,016				56,232	62,016
Consumer: Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				61				64	61	64
Charge-offs									(38)	(21)
Recoveries									2	1
Provisions									38	17
Ending balance	63				61				63	61
Ending balance: individually evaluated for impairment	12				5				12	5
Ending balance: collectively evaluated for impairment	51				56				51	56
Ending balance: Loans receivables	5,677				5,972				5,677	5,972
Ending Balance: individually evaluated for impairment	245				256				245	256
Ending Balance: collectively evaluated for impairment	5,432				5,716				5,432	5,716
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				$ 558				$ 527	558	527
Provisions									(11)	31
Ending balance	547				558				547	558
Ending balance: collectively evaluated for impairment	$ 547				$ 558				$ 547	$ 558