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Allowance for Credit Losses - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses and unfunded lending-related commitments losses	$ 471,334	$ 460,205	$ 447,941	$ 436,603
Allowance for held-to-maturity securities losses	257	260	446
Allowance for credit losses	471,591	460,465	448,387
Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses and unfunded lending-related commitments losses	390,651	379,283	378,207
Unfunded lending-related commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses and unfunded lending-related commitments losses	80,683	80,922	69,734
Loans and unfunded lending-related commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses and unfunded lending-related commitments losses	$ 471,334	$ 460,205	$ 447,941