Allowance for Loan Losses (Allowance for Loan Losses Rollforward Analysis) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		$ 27,398	$ 26,174	$ 27,072	$ 26,488
Charge-offs		(966)	(96)	(1,888)	(889)
Recoveries		165	81	238	160
Provision		400	350	1,575	750
Allowance, Ending Balance		26,997	26,509	26,997	26,509
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	[1]	16,882	12,443	15,381	12,729
Charge-offs	[1]	(947)	0	(947)	(627)
Recoveries	[1]	0	0	0	25
Provision	[1]	866	1,052	2,367	1,368
Allowance, Ending Balance	[1]	16,801	13,495	16,801	13,495
Commercial & Industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	[2]	4,453	6,642	5,847	5,580
Charge-offs	[2]	(1)	(1)	(19)	(8)
Recoveries	[2]	123	71	151	104
Provision	[2]	(1,128)	535	(2,532)	1,571
Allowance, Ending Balance	[2]	3,447	7,247	3,447	7,247
Total Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		21,335	19,085	21,228	18,309
Charge-offs		(948)	(1)	(966)	(635)
Recoveries		123	71	151	129
Provision		(262)	1,587	(165)	2,939
Allowance, Ending Balance		20,248	20,742	20,248	20,742
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		4,857	5,314	3,987	5,427
Charge-offs		0	(68)	(486)	(73)
Recoveries		0	0	0	0
Provision		554	(1,131)	1,910	(1,239)
Allowance, Ending Balance		5,411	4,115	5,411	4,115
Home Equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		913	1,375	1,603	2,412
Charge-offs		0	0	(372)	(111)
Recoveries		36	2	71	12
Provision		64	12	(289)	(924)
Allowance, Ending Balance		1,013	1,389	1,013	1,389
Other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		293	400	254	340
Charge-offs		(18)	(27)	(64)	(70)
Recoveries		6	8	16	19
Provision		44	(118)	119	(26)
Allowance, Ending Balance		325	263	325	263
Total Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		1,206	1,775	1,857	2,752
Charge-offs		(18)	(27)	(436)	(181)
Recoveries		42	10	87	31
Provision		108	(106)	(170)	(950)
Allowance, Ending Balance		$ 1,338	$ 1,652	$ 1,338	$ 1,652

[1] Commercial real estate loans.

[2] Commercial & industrial loans.