Loans And Allowance for Credit Losses (Credit Quality Indicators Personal Banking Loan Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Credit Quality Indicator [Line Items]
Loans charged off	$ 13,293	$ 11,165
Personal Banking Portfolio Segment [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	217,938		$ 818,417
Fiscal Year before Current Fiscal Year	733,388		758,825
Two Years before Current Fiscal Year	718,215		634,706
Three Years before Current Fiscal Year	601,649		649,974
Four Years before Current Fiscal Year	613,095		712,656
Prior	1,444,879		790,211
Revolving Loans Amortized Cost Basis	1,762,774		1,730,375
Total	6,091,938		6,095,164
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	686		4,127
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	1,139		3,191
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	957		2,974
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	698		1,391
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	265		540
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	140		277
Financing Receivable, Revolving, Writeoff	8,682		32,736
Loans charged off	12,567	$ 10,849	45,236
Personal Banking Portfolio Segment [Member] | Personal Real Estate Loan [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	75,510		387,784
Fiscal Year before Current Fiscal Year	370,932		388,386
Two Years before Current Fiscal Year	378,485		406,111
Three Years before Current Fiscal Year	398,412		484,731
Four Years before Current Fiscal Year	475,499		640,295
Prior	1,340,073		739,954
Revolving Loans Amortized Cost Basis	8,898		10,934
Total	3,047,809		3,058,195
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0		82
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	45		115
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	35		83
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0		22
Financing Receivable, Revolving, Writeoff	0		0
Loans charged off	80		302
Personal Banking Portfolio Segment [Member] | Consumer Loan [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	139,297		419,367
Fiscal Year before Current Fiscal Year	362,456		370,439
Two Years before Current Fiscal Year	339,730		228,595
Three Years before Current Fiscal Year	203,237		165,243
Four Years before Current Fiscal Year	137,596		72,361
Prior	104,806		50,257
Revolving Loans Amortized Cost Basis	829,038		766,861
Total	2,116,160		2,073,123
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0		1,438
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	1,139		3,109
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	912		2,859
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	663		1,308
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	265		540
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	140		255
Financing Receivable, Revolving, Writeoff	511		2,309
Loans charged off	3,630		11,818
Personal Banking Portfolio Segment [Member] | Revolving home equity
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	356,675		356,650
Total	356,675		356,650
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Revolving, Writeoff	0		0
Loans charged off	0		0
Personal Banking Portfolio Segment [Member] | Credit Card Receivable [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	568,163		595,930
Total	568,163		595,930
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Revolving, Writeoff	8,171		30,427
Loans charged off	8,171		30,427
Personal Banking Portfolio Segment [Member] | Overdrafts
Credit Quality Indicator [Line Items]
Current Fiscal Year	3,131		11,266
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	0		0
Total	3,131		11,266
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	686		2,689
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0		0
Financing Receivable, Revolving, Writeoff	0		0
Loans charged off	686		2,689
Personal Banking Portfolio Segment [Member] | Current to 90 Days Past Due
Credit Quality Indicator [Line Items]
Current Fiscal Year	217,938		817,287
Fiscal Year before Current Fiscal Year	732,930		757,341
Two Years before Current Fiscal Year	717,262		632,869
Three Years before Current Fiscal Year	600,682		647,763
Four Years before Current Fiscal Year	611,498		709,429
Prior	1,439,590		786,107
Revolving Loans Amortized Cost Basis	1,750,311		1,717,413
Total	6,070,211		6,068,209
Personal Banking Portfolio Segment [Member] | Current to 90 Days Past Due | Personal Real Estate Loan [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	75,510		387,119
Fiscal Year before Current Fiscal Year	370,737		387,486
Two Years before Current Fiscal Year	377,835		404,680
Three Years before Current Fiscal Year	397,730		482,733
Four Years before Current Fiscal Year	474,009		637,115
Prior	1,335,077		736,217
Revolving Loans Amortized Cost Basis	8,898		10,934
Total	3,039,796		3,046,284
Personal Banking Portfolio Segment [Member] | Current to 90 Days Past Due | Consumer Loan [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	139,297		418,902
Fiscal Year before Current Fiscal Year	362,193		369,855
Two Years before Current Fiscal Year	339,427		228,189
Three Years before Current Fiscal Year	202,952		165,030
Four Years before Current Fiscal Year	137,489		72,314
Prior	104,513		49,890
Revolving Loans Amortized Cost Basis	827,546		765,333
Total	2,113,417		2,069,513
Personal Banking Portfolio Segment [Member] | Current to 90 Days Past Due | Revolving home equity
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	354,156		353,854
Total	354,156		353,854
Personal Banking Portfolio Segment [Member] | Current to 90 Days Past Due | Credit Card Receivable [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	559,711		587,292
Total	559,711		587,292
Personal Banking Portfolio Segment [Member] | Current to 90 Days Past Due | Overdrafts
Credit Quality Indicator [Line Items]
Current Fiscal Year	3,131		11,266
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	0		0
Total	3,131		11,266
Personal Banking Portfolio Segment [Member] | Over 90 days past due
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		1,130
Fiscal Year before Current Fiscal Year	458		1,476
Two Years before Current Fiscal Year	946		1,837
Three Years before Current Fiscal Year	967		2,103
Four Years before Current Fiscal Year	1,490		3,227
Prior	4,414		3,194
Revolving Loans Amortized Cost Basis	10,486		10,985
Total	18,761		23,952
Personal Banking Portfolio Segment [Member] | Over 90 days past due | Personal Real Estate Loan [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		665
Fiscal Year before Current Fiscal Year	195		892
Two Years before Current Fiscal Year	643		1,431
Three Years before Current Fiscal Year	682		1,890
Four Years before Current Fiscal Year	1,383		3,180
Prior	4,121		2,827
Revolving Loans Amortized Cost Basis	0		0
Total	7,024		10,885
Personal Banking Portfolio Segment [Member] | Over 90 days past due | Consumer Loan [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		465
Fiscal Year before Current Fiscal Year	263		584
Two Years before Current Fiscal Year	303		406
Three Years before Current Fiscal Year	285		213
Four Years before Current Fiscal Year	107		47
Prior	293		367
Revolving Loans Amortized Cost Basis	1,492		1,528
Total	2,743		3,610
Personal Banking Portfolio Segment [Member] | Over 90 days past due | Revolving home equity
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	542		819
Total	542		819
Personal Banking Portfolio Segment [Member] | Over 90 days past due | Credit Card Receivable [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	8,452		8,638
Total	8,452		8,638
Personal Banking Portfolio Segment [Member] | Non-Accrual [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		8
Two Years before Current Fiscal Year	7		0
Three Years before Current Fiscal Year	0		108
Four Years before Current Fiscal Year	107		0
Prior	875		910
Revolving Loans Amortized Cost Basis	1,977		1,977
Total	2,966		3,003
Personal Banking Portfolio Segment [Member] | Non-Accrual [Member] | Personal Real Estate Loan [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		8
Two Years before Current Fiscal Year	7		0
Three Years before Current Fiscal Year	0		108
Four Years before Current Fiscal Year	107		0
Prior	875		910
Revolving Loans Amortized Cost Basis	0		0
Total	989		1,026
Personal Banking Portfolio Segment [Member] | Non-Accrual [Member] | Revolving home equity
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	0		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	1,977		1,977
Total	$ 1,977		$ 1,977