Loans and Allowance for Credit Losses (Allowance for Credit Losses on Financing Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Allowance for credit losses:
Beginning balance	$ 8,358	$ 7,917	$ 8,316	$ 7,695
Charge-offs	(568)	(641)	(1,578)	(1,991)
Recoveries	219	412	446	794
Net charge-offs	(349)	(229)	(1,132)	(1,197)
Provision	605	410	1,430	1,600
Ending balance	8,614	8,098	8,614	8,098
Commercial and Residential Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Allowance for credit losses:
Beginning balance	1,744	1,852	1,646	1,303
Charge-offs	(9)	(479)	(263)	(1,058)
Recoveries	8	9	24	116
Net charge-offs	(1)	(470)	(239)	(942)
Provision	275	460	611	1,481
Ending balance	2,018	1,842	2,018	1,842
Residential Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	2,035	2,318	2,181	2,834
Charge-offs	(407)	(26)	(525)	(283)
Recoveries	121	102	188	247
Net charge-offs	(286)	76	(337)	(36)
Provision	331	(103)	236	(507)
Ending balance	2,080	2,291	2,080	2,291
Commercial Real Estate Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	2,871	2,616	2,999	2,379
Charge-offs			(503)	(320)
Recoveries	10	233	20	248
Net charge-offs	10	233	(483)	(72)
Provision	306	(38)	671	504
Ending balance	3,187	2,811	3,187	2,811
Commercial Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	677	505	558	448
Charge-offs	(139)	(136)	(264)	(285)
Recoveries	79	60	201	142
Net charge-offs	(60)	(76)	(63)	(143)
Provision	300	70	422	194
Ending balance	917	499	917	499
Consumer Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	206	168	156	229
Charge-offs	(13)		(23)	(45)
Recoveries	1	8	13	41
Net charge-offs	(12)	8	(10)	(4)
Provision	(40)	(20)	8	(69)
Ending balance	154	156	154	156
Unallocated Financing Receivables [Member]
Allowance for credit losses:
Beginning balance	825	458	776	502
Provision	(567)	41	(518)	(3)
Ending balance	$ 258	$ 499	$ 258	$ 499