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Loans - Schedule of Loan Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
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%

X

- 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

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X

- Definition

Loans [Line Items]

+ References

No definition available.

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- Definition

Percentage of Loans and Leases Receivable, Gross, Carrying Amount

+ References

No definition available.

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