Loans - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Loans [Line Items]
Net deferred loan fees and costs and fair value purchase accounting adjustments	$ 78,200	$ 84,200
Outstanding borrowings from FHLB	3,151,309	2,326,071
Federal Agency Borrowings
Loans [Line Items]
Loans pledged as collateral	23,700,000	21,100,000
Federal Home Loan Bank Advances
Loans [Line Items]
Loans pledged as collateral	15,100,000
Federal Reserve Bank Advances
Loans [Line Items]
Loans pledged as collateral	8,600,000
Premium finance receivables
Loans [Line Items]
Unearned income portions of premium finance receivables	$ 267,700	$ 285,400

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Fair value of the securities pledged as collateral against securities loaned.

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