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Commitments and Contingencies and Related-Party Transactions (Schedule Of Commitments And Contingencies) (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Loss Contingencies [Line Items]
Commitments and contingent liabilities
Commitments to extend credit
Loss Contingencies [Line Items]
Commitments and contingent liabilities	9,983,817	10,077,780
Forward sales commitments
Loss Contingencies [Line Items]
Commitments and contingent liabilities	83,250	76,535
Commitments to originate residential mortgage loans held for sale
Loss Contingencies [Line Items]
Commitments and contingent liabilities	56,633	46,208
Standby letters of credit
Loss Contingencies [Line Items]
Commitments and contingent liabilities	$ 242,725	$ 216,422

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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