Loans (Credit Quality Indicators Vintage) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	$ 974,144	$ 1,058,859
Term loans amortized cost, prior year	751,669	734,581
Term loans amortized cost, two years ago	622,902	554,968
Term loans amortized cost, three years ago	452,292	476,043
Term loans amortized cost, four years ago	353,034	325,496
Term loans amortized cost, five years ago or more	809,521	699,479
Revolving loans amortized cost	310,554	330,433
Revolving loans converted to term loans	12,288	16,131
Total	4,286,404	4,195,990
Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	266,040	285,054
Term loans amortized cost, prior year	255,402	374,110
Term loans amortized cost, two years ago	335,162	300,304
Term loans amortized cost, three years ago	252,887	252,532
Term loans amortized cost, four years ago	195,709	147,808
Term loans amortized cost, five years ago or more	345,476	259,726
Revolving loans amortized cost	8,830	11,104
Revolving loans converted to term loans	2,279	2,386
Total	1,661,785	1,633,024
Commercial Real Estate | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	260,038	283,341
Term loans amortized cost, prior year	250,606	353,875
Term loans amortized cost, two years ago	305,492	260,917
Term loans amortized cost, three years ago	215,877	236,310
Term loans amortized cost, four years ago	179,618	136,490
Term loans amortized cost, five years ago or more	322,267	249,359
Revolving loans amortized cost	8,466	10,333
Revolving loans converted to term loans	2,279	2,386
Total	1,544,643	1,533,011
Commercial Real Estate | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	6,002	756
Term loans amortized cost, prior year	786	20,235
Term loans amortized cost, two years ago	29,670	39,387
Term loans amortized cost, three years ago	37,010	16,222
Term loans amortized cost, four years ago	16,091	11,318
Term loans amortized cost, five years ago or more	23,209	10,367
Revolving loans amortized cost	364	771
Revolving loans converted to term loans	0	0
Total	113,132	99,056
Commercial Real Estate | Classified [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	0	957
Term loans amortized cost, prior year	4,010	0
Term loans amortized cost, two years ago	0	0
Term loans amortized cost, three years ago	0	0
Term loans amortized cost, four years ago	0	0
Term loans amortized cost, five years ago or more	0	0
Revolving loans amortized cost	0	0
Revolving loans converted to term loans	0	0
Total	4,010	957
Commercial & Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	120,412	295,019
Term loans amortized cost, prior year	96,441	96,497
Term loans amortized cost, two years ago	107,294	101,356
Term loans amortized cost, three years ago	95,236	63,631
Term loans amortized cost, four years ago	58,859	47,586
Term loans amortized cost, five years ago or more	115,249	112,344
Revolving loans amortized cost	88,187	99,623
Revolving loans converted to term loans	1,096	1,352
Total	682,774	817,408
Commercial & Industrial | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	120,412	293,493
Term loans amortized cost, prior year	96,441	95,775
Term loans amortized cost, two years ago	106,652	98,146
Term loans amortized cost, three years ago	90,595	56,792
Term loans amortized cost, four years ago	52,440	44,445
Term loans amortized cost, five years ago or more	99,439	91,128
Revolving loans amortized cost	87,001	95,817
Revolving loans converted to term loans	1,096	1,296
Total	654,076	776,892
Commercial & Industrial | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	0	1,123
Term loans amortized cost, prior year	0	722
Term loans amortized cost, two years ago	642	3,210
Term loans amortized cost, three years ago	4,641	6,839
Term loans amortized cost, four years ago	6,419	3,141
Term loans amortized cost, five years ago or more	13,019	14,853
Revolving loans amortized cost	1,186	3,806
Revolving loans converted to term loans	0	56
Total	25,907	33,750
Commercial & Industrial | Classified [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	0	403
Term loans amortized cost, prior year	0	0
Term loans amortized cost, two years ago	0	0
Term loans amortized cost, three years ago	0	0
Term loans amortized cost, four years ago	0	0
Term loans amortized cost, five years ago or more	2,791	6,363
Revolving loans amortized cost	0	0
Revolving loans converted to term loans	0	0
Total	2,791	6,766
Residential Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	573,380	463,715
Term loans amortized cost, prior year	388,586	254,926
Term loans amortized cost, two years ago	174,750	148,149
Term loans amortized cost, three years ago	100,779	156,862
Term loans amortized cost, four years ago	96,557	128,249
Term loans amortized cost, five years ago or more	338,312	315,411
Revolving loans amortized cost	0	0
Revolving loans converted to term loans	0	0
Total	1,672,364	1,467,312
Residential Real Estate | Current [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	573,380	463,477
Term loans amortized cost, prior year	387,179	253,228
Term loans amortized cost, two years ago	174,478	146,839
Term loans amortized cost, three years ago	99,480	155,976
Term loans amortized cost, four years ago	95,794	128,139
Term loans amortized cost, five years ago or more	333,355	309,314
Revolving loans amortized cost	0	0
Revolving loans converted to term loans	0	0
Total	1,663,666	1,456,973
Residential Real Estate | Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	0	238
Term loans amortized cost, prior year	1,407	1,698
Term loans amortized cost, two years ago	272	1,310
Term loans amortized cost, three years ago	1,299	886
Term loans amortized cost, four years ago	763	110
Term loans amortized cost, five years ago or more	4,957	6,097
Revolving loans amortized cost	0	0
Revolving loans converted to term loans	0	0
Total	8,698	10,339
Home Equity
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	8,170	9,838
Term loans amortized cost, prior year	7,294	6,806
Term loans amortized cost, two years ago	4,315	3,922
Term loans amortized cost, three years ago	2,682	1,474
Term loans amortized cost, four years ago	1,125	1,217
Term loans amortized cost, five years ago or more	4,124	4,141
Revolving loans amortized cost	213,251	219,395
Revolving loans converted to term loans	8,913	12,392
Total	249,874	259,185
Home Equity | Current [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	8,170	9,838
Term loans amortized cost, prior year	7,294	6,771
Term loans amortized cost, two years ago	4,315	3,898
Term loans amortized cost, three years ago	2,682	1,474
Term loans amortized cost, four years ago	1,125	1,217
Term loans amortized cost, five years ago or more	3,939	3,955
Revolving loans amortized cost	213,010	219,085
Revolving loans converted to term loans	8,515	11,280
Total	249,050	257,518
Home Equity | Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	0	0
Term loans amortized cost, prior year	0	35
Term loans amortized cost, two years ago	0	24
Term loans amortized cost, three years ago	0	0
Term loans amortized cost, four years ago	0	0
Term loans amortized cost, five years ago or more	185	186
Revolving loans amortized cost	241	310
Revolving loans converted to term loans	398	1,112
Total	824	1,667
Other
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	6,142	5,233
Term loans amortized cost, prior year	3,946	2,242
Term loans amortized cost, two years ago	1,381	1,237
Term loans amortized cost, three years ago	708	1,544
Term loans amortized cost, four years ago	784	636
Term loans amortized cost, five years ago or more	6,360	7,857
Revolving loans amortized cost	286	311
Revolving loans converted to term loans	0	1
Total	19,607	19,061
Other | Current [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	6,128	5,214
Term loans amortized cost, prior year	3,936	2,241
Term loans amortized cost, two years ago	1,381	1,237
Term loans amortized cost, three years ago	708	1,544
Term loans amortized cost, four years ago	784	548
Term loans amortized cost, five years ago or more	6,360	7,850
Revolving loans amortized cost	286	308
Revolving loans converted to term loans	0	1
Total	19,583	18,943
Other | Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Term loans amortized cost, current year	14	19
Term loans amortized cost, prior year	10	1
Term loans amortized cost, two years ago	0	0
Term loans amortized cost, three years ago	0	0
Term loans amortized cost, four years ago	0	88
Term loans amortized cost, five years ago or more	0	7
Revolving loans amortized cost	0	3
Revolving loans converted to term loans	0	0
Total	$ 24	$ 118