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Loans and Allowance for Credit Losses, Loans by Portfolio Type (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Loan receivables disclosure [Abstract] |  |
Loans, fixed rate of interest | $ 6,966,562 | $ 6,739,706
Loans, variable rate of interest | 17,826,238 | 17,328,293
Nonaccrual | 72,394 | 46,725
Total | 24,865,194 | 24,114,724
Credit Commitments [Abstract] |  |
Outstanding commitments to extend credit | 15,300,000 |
Outstanding standby letters of credit | 643,000 |
Commercial [Member] |  |
Loan receivables disclosure [Abstract] |  |
Loans, fixed rate of interest | 3,400,985 | 3,450,238
Loans, variable rate of interest | 11,079,685 | 11,565,251
Nonaccrual | 32,270 | 14,647
Total | 14,512,940 | 15,030,136
Commercial real estate [Member] |  |
Loan receivables disclosure [Abstract] |  |
Loans, fixed rate of interest | 659,296 | 668,532
Loans, variable rate of interest | 5,086,502 | 4,380,015
Nonaccrual | 6,809 | 9,905
Total | 5,752,607 | 5,058,452
Loans to individuals [Member] |  |
Loan receivables disclosure [Abstract] |  |
Loans, fixed rate of interest | 2,906,281 | 2,620,936
Loans, variable rate of interest | 1,660,051 | 1,383,027
Nonaccrual | 33,315 | 22,173
Total | $ 4,599,647 | $ 4,026,136

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