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Loans And Allowance For Credit Losses (Aging Information On Past Due And Accruing Loans) (Details) - USD ($) $ in Thousands | Mar. 31, 2026 | Dec. 31, 2025
--- | --- | ---
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | $ 20,367,082 | $ 17,648,771
30 - 89 Days Past Due | 60,238 | 82,083
90 Days Past Due and Still Accruing | 22,824 | 24,659
Non-accrual loans | 10,920 | 15,750
Total | 20,461,064 | 17,771,263
Business Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 6,750,356 | 6,439,380
Real estate - construction and land |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 1,581,789 | 1,438,012
Business Real Estate Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 4,059,539 | 3,674,567
Personal Real Estate Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 4,407,606 | 3,053,435
Consumer Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 2,475,353 | 2,196,822
Revolving home equity |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 619,178 | 375,159
Credit Card Receivable [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 557,733 | 589,694
Overdrafts |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 9,510 | 4,194
Commercial Portfolio Segment [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 12,391,684 | 11,551,959
Commercial Portfolio Segment [Member] | Business Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 6,745,956 | 6,437,476
30 - 89 Days Past Due | 3,640 | 1,241
90 Days Past Due and Still Accruing | 559 | 540
Non-accrual loans | 201 | 123
Total | 6,750,356 | 6,439,380
Commercial Portfolio Segment [Member] | Real estate - construction and land |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 1,581,250 | 1,437,727
30 - 89 Days Past Due | 361 | 285
90 Days Past Due and Still Accruing | 178 | 0
Non-accrual loans | 0 | 0
Total | 1,581,789 | 1,438,012
Commercial Portfolio Segment [Member] | Business Real Estate Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 4,045,538 | 3,636,517
30 - 89 Days Past Due | 4,435 | 23,265
90 Days Past Due and Still Accruing | 197 | 0
Non-accrual loans | 9,369 | 14,785
Total | 4,059,539 | 3,674,567
Personal Banking Portfolio Segment [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Total | 8,069,380 | 6,219,304
Personal Banking Portfolio Segment [Member] | Personal Real Estate Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 4,376,280 | 3,021,212
30 - 89 Days Past Due | 20,721 | 19,450
90 Days Past Due and Still Accruing | 9,289 | 11,931
Non-accrual loans | 1,316 | 842
Total | 4,407,606 | 3,053,435
Personal Banking Portfolio Segment [Member] | Consumer Loan [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 2,452,149 | 2,165,109
30 - 89 Days Past Due | 20,337 | 28,269
90 Days Past Due and Still Accruing | 2,867 | 3,444
Non-accrual loans | 0 | 0
Total | 2,475,353 | 2,196,822
Personal Banking Portfolio Segment [Member] | Revolving home equity |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 614,338 | 373,245
30 - 89 Days Past Due | 3,453 | 1,493
90 Days Past Due and Still Accruing | 1,353 | 421
Non-accrual loans | 34 | 0
Total | 619,178 | 375,159
Personal Banking Portfolio Segment [Member] | Credit Card Receivable [Member] |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 542,359 | 573,698
30 - 89 Days Past Due | 6,993 | 7,673
90 Days Past Due and Still Accruing | 8,381 | 8,323
Non-accrual loans | 0 | 0
Total | 557,733 | 589,694
Personal Banking Portfolio Segment [Member] | Overdrafts |  |
Loans And Allowance For Loan Losses [Line Items] |  |
Current or Less than 30 Days Past Due | 9,212 | 3,787
30 - 89 Days Past Due | 298 | 407
90 Days Past Due and Still Accruing | 0 | 0
Non-accrual loans | 0 | 0
Total | $ 9,510 | $ 4,194

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