Loans and Allowance for Credit Losses (Narrative) (Details)	3 Months Ended
Mar. 31, 2024 USD ($) Loan	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Accrued interest	$ 125,400,000		$ 124,700,000
Percentage of baseline economic forecast	40.00%	40.00%
Description of post modification defaults	A payment default occurs if the loan is either 90 days or more delinquent or has been charged off as of the end of the period presented.
Nonaccrual loans	$ 82,082,000		59,036,000
Loans held for sale	16,470,000		26,124,000
Modified Loans To Borrowers Experiencing Financial Difficulty [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	200,000		100,000
Accruing and nonaccruing	37,600,000		24,500,000
Unfunded commitment to borrowers related to MEFD or TDR	$ 10,800,000		700,000
Moderate Recessionary Scenario S-3 [Member]
Accounts Notes And Loans Receivable [Line Items]
Percentage of baseline economic forecast		10.00%
Downside Mild Recessionary S-2 [Member]
Accounts Notes And Loans Receivable [Line Items]
Percentage of baseline economic forecast	60.00%	50.00%
Residential Mortgages [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	$ 25,924,000		26,137,000
Loans carried at fair value option	15,200,000		13,300,000
Unpaid principal balance	14,800,000		12,900,000
Consumer [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	10,180,000		8,555,000
Real estate in process of foreclosure	6,100,000		7,100,000
Real estate acquired through foreclosure	800,000		1,600,000
Total Commercial And Industrial [Member] \| Total Commercial [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	$ 19,684,000		23,068,000
Commercial Non-Real Estate [Member] \| Consumer [Member]
Accounts Notes And Loans Receivable [Line Items]
Number of contracts subsequently defaulted \| Loan	3
Recorded Investment	$ 3,200,000	$ 0
Commercial Non-Real Estate [Member] \| Total Commercial And Industrial [Member] \| Total Commercial [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	$ 17,487,000		$ 20,840,000

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