Allowance For Loan Losses And Credit Quality Of Financing Receivables - Credit Risk Profile By Creditworthiness (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	$ 773,217	$ 696,142
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	40,802	40,280
Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	41,213	25,360
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	526,054	479,227
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	164,181	150,237
Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	967	1,038
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	754,919	678,060
Pass [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	40,684	40,247
Pass [Member] | Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	41,213	25,360
Pass [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	510,655	463,889
Pass [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	161,400	147,526
Pass [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	967	1,038
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	7,023	8,045
Special Mention [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	98	0
Special Mention [Member] | Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Special Mention [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	6,461	7,461
Special Mention [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	464	584
Special Mention [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	11,275	10,037
Substandard [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	20	33
Substandard [Member] | Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Substandard [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	8,938	7,877
Substandard [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	2,317	2,127
Substandard [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Doubtful [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Doubtful [Member] | Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Doubtful [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Doubtful [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	0	0
Doubtful [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans receivable	$ 0	$ 0