Loans - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Loans [Line Items]
Net deferred loan fees and costs and fair value purchase accounting adjustments	$ 84,200	$ 71,800
Outstanding borrowings from FHLB	2,326,071	2,316,071
Federal Agency Borrowings
Loans [Line Items]
Loans pledged as collateral	21,100,000	8,200,000
Federal Home Loan Bank Advances
Loans [Line Items]
Loans pledged as collateral	12,800,000
Federal Reserve Bank Advances
Loans [Line Items]
Loans pledged as collateral	8,300,000
Premium finance receivables
Loans [Line Items]
Unearned income portions of premium finance receivables	$ 285,400	$ 224,500

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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