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

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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