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Loans and Allowance for Credit Losses (Schedule of Loans by Risk Rating Category) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	$ 23,702,494	$ 24,297,980
Criticized Commercial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	1,225,843	1,383,755
Criticized Commercial Portfolio Segment | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	136,640	262,387
Criticized Commercial Portfolio Segment | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	733,615	894,754
Criticized Commercial Portfolio Segment | Substandard Non-Accruing
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	306,953	219,758
Criticized Commercial Portfolio Segment | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	$ 48,635	$ 6,856

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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

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