Allowance For Loan Losses (Schedule Of Aging Analysis Of Accruing And Non-Accruing Loans) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 2,606,134	$ 2,626,094
30 - 59 days past due	7,701	7,734
60 - 89 days past due	687	1,239
Over 90 days past due	383	423
Financing Receivable, Acquired with Deteriorated Credit Quality, Recorded Investment, Past Due	1,383	1,270
Non-accrual	16,183	15,306
Total	2,632,471	2,652,066
Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	1,294,841	1,286,306
30 - 59 days past due	5,276	4,949
60 - 89 days past due	597	758
Over 90 days past due	245	169
Non-accrual	2,299	2,394
Total	1,303,258	1,294,576
Home equity - junior lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	142,949	144,788
30 - 59 days past due	557	563
60 - 89 days past due	71	155
Over 90 days past due	1	30
Non-accrual	92	68
Total	143,670	145,604
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	120,393	131,073
30 - 59 days past due	558	243
60 - 89 days past due	0	0
Over 90 days past due	45	210
Financing Receivable, Acquired with Deteriorated Credit Quality, Recorded Investment, Past Due	0	0
Non-accrual	3,346	1,115
Total	124,342	132,641
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	1,006,799	1,022,158
30 - 59 days past due	934	1,371
60 - 89 days past due	0	210
Over 90 days past due	0	0
Financing Receivable, Acquired with Deteriorated Credit Quality, Recorded Investment, Past Due	1,383	1,270
Non-accrual	10,446	11,729
Total	1,019,562	1,036,738
Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	38,164	39,286
30 - 59 days past due	164	291
60 - 89 days past due	16	114
Over 90 days past due	92	14
Non-accrual	0	0
Total	38,436	39,705
Demand Deposit Account Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	2,988	2,483
30 - 59 days past due	212	317
60 - 89 days past due	3	2
Over 90 days past due	0	0
Non-accrual	0	0
Total	3,203	2,802
Noncommercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,488,567	1,482,687
Originated Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	2,360,162	2,376,849
30 - 59 days past due	5,015	5,811
60 - 89 days past due	445	993
Over 90 days past due	158	410
Non-accrual	11,818	9,735
Total	2,377,598	2,393,798
Originated Loans [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	1,211,870	1,200,177
30 - 59 days past due	3,876	4,235
60 - 89 days past due	371	758
Over 90 days past due	79	169
Non-accrual	2,213	2,259
Total	1,218,409	1,207,598
Originated Loans [Member] | Home equity - junior lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	140,763	142,624
30 - 59 days past due	471	561
60 - 89 days past due	71	155
Over 90 days past due	1	30
Non-accrual	92	68
Total	141,398	143,438
Originated Loans [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	109,661	120,950
30 - 59 days past due	113	100
60 - 89 days past due	0	0
Over 90 days past due	0	210
Non-accrual	2,924	78
Total	112,698	121,338
Originated Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	862,315	877,437
30 - 59 days past due	299	479
60 - 89 days past due	0	0
Over 90 days past due	0	0
Non-accrual	6,589	7,330
Total	869,203	885,246
Originated Loans [Member] | Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	32,565	33,178
30 - 59 days past due	44	119
60 - 89 days past due	0	78
Over 90 days past due	78	1
Non-accrual	0	0
Total	32,687	33,376
Originated Loans [Member] | Demand Deposit Account Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	2,988	2,483
30 - 59 days past due	212	317
60 - 89 days past due	3	2
Over 90 days past due	0	0
Non-accrual	0	0
Total	3,203	2,802
Acquired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	245,972	249,245
30 - 59 days past due	2,686	1,923
60 - 89 days past due	242	246
Over 90 days past due	225	13
Financing Receivable, Acquired with Deteriorated Credit Quality, Recorded Investment, Past Due	1,383	1,270
Non-accrual	4,365	5,571
Total	254,873	258,268
Acquired Loans [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	82,971	86,129
30 - 59 days past due	1,400	714
60 - 89 days past due	226	0
Over 90 days past due	166	0
Non-accrual	86	135
Total	84,849	86,978
Acquired Loans [Member] | Home equity - junior lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	2,186	2,164
30 - 59 days past due	86	2
60 - 89 days past due	0	0
Over 90 days past due	0	0
Non-accrual	0	0
Total	2,272	2,166
Acquired Loans [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	10,732	10,123
30 - 59 days past due	445	143
60 - 89 days past due	0	0
Over 90 days past due	45	0
Financing Receivable, Acquired with Deteriorated Credit Quality, Recorded Investment, Past Due	0	0
Non-accrual	422	1,037
Total	11,644	11,303
Acquired Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	144,484	144,721
30 - 59 days past due	635	892
60 - 89 days past due	0	210
Over 90 days past due	0	0
Financing Receivable, Acquired with Deteriorated Credit Quality, Recorded Investment, Past Due	1,383	1,270
Non-accrual	3,857	4,399
Total	150,359	151,492
Acquired Loans [Member] | Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	5,599	6,108
30 - 59 days past due	120	172
60 - 89 days past due	16	36
Over 90 days past due	14	13
Non-accrual	0	0
Total	5,749	6,329
Acquired Loans [Member] | Demand Deposit Account Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	0	0
30 - 59 days past due	0	0
60 - 89 days past due	0	0
Over 90 days past due	0	0
Non-accrual	0	0
Total	0	0
Performing [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,300,714	1,292,012
Performing [Member] | Home equity - junior lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	143,577	145,506
Performing [Member] | Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	38,344	39,692
Performing [Member] | Demand Deposit Account Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	3,203	2,802
Performing [Member] | Noncommercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,485,838	1,480,012
Nonperforming [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	2,544	2,564
Nonperforming [Member] | Home equity - junior lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	93	98
Nonperforming [Member] | Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	92	13
Nonperforming [Member] | Demand Deposit Account Overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	0	0
Nonperforming [Member] | Noncommercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 2,729	$ 2,675