Allowance For Loan Losses And Credit Quality Of Financing Receivables - Changes In The Allowance For Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 5,988	$ 5,752	$ 5,590	$ 5,641
Charge-offs	(127)	(125)	(383)	(578)
Recoveries	12	13	70	72
Provision	458	1	1,054	506
Ending balance	6,331	5,641	6,331	5,641
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	199	86	85	231
Charge-offs	0	0	(138)	(19)
Recoveries	5	5	21	10
Provision	5	(8)	241	(139)
Ending balance	209	83	209	83
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	208	277	220	383
Provision	106	(57)	94	(163)
Ending balance	314	220	314	220
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	4,020	3,613	3,646	3,491
Charge-offs	(91)	(119)	(156)	(542)
Recoveries	2	3	36	39
Provision	(24)	134	381	643
Ending balance	3,907	3,631	3,907	3,631
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	914	898	784	903
Charge-offs	(25)	0	(59)	0
Recoveries	1	4	7	17
Provision	(48)	26	110	8
Ending balance	842	928	842	928
Consumer And Other [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	17	86	87	19
Charge-offs	(11)	(6)	(30)	(17)
Recoveries	4	1	6	6
Provision	8	5	(45)	78
Ending balance	18	86	18	86
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	630	792	768	614
Provision	411	(99)	273	79
Ending balance	$ 1,041	$ 693	$ 1,041	$ 693