Allowance for Loan Losses Allowance for Loan Losses (Allowance for Loan Losses Rollforward Analysis) (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]
Allowance, Beginning Balance	$ 25,826	$ 27,587		$ 27,069	$ 28,023
Charge-offs	(2,055)	(725)		(4,390)	(1,401)
Recoveries	78	99		220	239
Provision	1,800	200		2,750	300
Allowance, Ending Balance	25,649	27,161		25,649	27,161
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	10,413	8,529		9,140	8,202
Charge-offs	(1,940)	0		(3,271)	(400)
Recoveries	4	4		21	88
Provision	1,981	(38)		4,568	605
Allowance, Ending Balance	10,458	8,495		10,458	8,495
Commercial Construction & Development [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	904	1,684		1,758	1,300
Charge-offs	0	0		0	0
Recoveries	0	0		0	0
Provision	78	5		(776)	389
Allowance, Ending Balance	982	1,689		982	1,689
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	6,520	7,010		8,202	7,987	[1]
Charge-offs	(3)	(378)		(757)	(429)	[1]
Recoveries	46	30		134	62	[1]
Provision	(59)	691		(1,075)	(267)	[1]
Allowance, Ending Balance	6,504	7,353	[1]	6,504	7,353	[1]
Commercial Segment [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	17,837	17,223		19,100	17,489
Charge-offs	(1,943)	(378)		(4,028)	(829)
Recoveries	50	34		155	150
Provision	2,000	658		2,717	727
Allowance, Ending Balance	17,944	17,537		17,944	17,537
Residential Segment [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	5,469	5,405		5,460	5,430
Charge-offs	(52)	(34)		(192)	(88)
Recoveries	5	22		9	26
Provision	(21)	150		124	175
Allowance, Ending Balance	5,401	5,543		5,401	5,543
Consumer Segment [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	2,520	2,683		2,509	2,713
Charge-offs	(60)	(313)		(170)	(484)
Recoveries	23	43		56	63
Provision	(179)	(164)		(91)	(43)
Allowance, Ending Balance	$ 2,304	2,249		$ 2,304	2,249
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance		2,276			2,391
Charge-offs		0			0
Recoveries		0			0
Provision		(444)			(559)
Allowance, Ending Balance		$ 1,832			$ 1,832

[1] Commercial & industrial loans.