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Loans - Schedule of Loan Portfolio (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
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Loans [Line Items] |  |
Total loans, net of unearned income | $ 53,105,101 | $ 48,055,037
Total loans, net of unearned income, percentage | 100.00% | 100.00%
Commercial |  |
Loans [Line Items] |  |
Total loans, net of unearned income | $ 17,044,686 | $ 15,574,551
Total loans, net of unearned income, percentage | 32.00% | 32.00%
Commercial real estate |  |
Loans [Line Items] |  |
Total loans, net of unearned income | $ 13,940,736 | $ 12,903,944
Total loans, net of unearned income, percentage | 26.00% | 27.00%
Home equity |  |
Loans [Line Items] |  |
Total loans, net of unearned income | $ 480,525 | $ 445,028
Total loans, net of unearned income, percentage | 1.00% | 1.00%
Residential real estate |  |
Loans [Line Items] |  |
Total loans, net of unearned income | $ 4,317,232 | $ 3,612,765
Total loans, net of unearned income, percentage | 8.00% | 8.00%
Premium finance receivables—property & casualty | Premium finance receivables—property & casualty |  |
Loans [Line Items] |  |
Total loans, net of unearned income | $ 8,183,416 | $ 7,272,042
Total loans, net of unearned income, percentage | 16.00% | 15.00%
Premium finance receivables—property & casualty | Premium finance receivables—life insurance |  |
Loans [Line Items] |  |
Total loans, net of unearned income | $ 9,023,642 | $ 8,147,145
Total loans, net of unearned income, percentage | 17.00% | 17.00%
Consumer and other |  |
Loans [Line Items] |  |
Total loans, net of unearned income | $ 114,864 | $ 99,562
Total loans, net of unearned income, percentage | 0.00% | 0.00%

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- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 + Details
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