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Loans (Narrative) (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Loans [Line Items] |  |
Net deferred loan fees and costs and fair value purchase accounting adjustments | $ 71,800 | $ 50,800
Outstanding borrowings from FHLB | 2,316,071 | 1,241,071
Federal Agency Borrowings |  |
Loans [Line Items] |  |
Loans pledged as collateral | 8,200,000 | 8,000,000
Federal Home Loan Bank Advances |  |
Loans [Line Items] |  |
Loans pledged as collateral | 7,800,000 |
Federal Reserve Bank Advances |  |
Loans [Line Items] |  |
Loans pledged as collateral | 409,100 |
Premium finance receivables |  |
Loans [Line Items] |  |
Unearned income portions of premium finance receivables | $ 224,500 | $ 135,500

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