Loans and Allowance for Credit Losses (Narrative) (Details)	9 Months Ended		12 Months Ended
	Sep. 30, 2022 USD ($) Loan	Sep. 30, 2021 USD ($) Loan	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Accrued interest	$ 82,500,000					$ 67,800,000
Base line economic forecast probability percentage	25.00%
Unemployment percentage rate forecast	3.50%
Labor force participation forecast percentage	62.50%
Prime age employment to population ratio above	80.00%
Federal funds rate description	Federal Funds rate will reach a target rate of 3.5% by the end of 2022, with the possibility of future rate increases; rate cuts not forecasted to begin until 2025
Nonaccrual loans	$ 39,807,000					55,523,000
TDRs both accruing and nonaccruing	4,800,000					10,600,000
Unfunded commitment to borrowers related to modified TDR	0					0
Loans held for sale	33,008,000					93,069,000
Troubled Debt Restructurings [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	2,800,000					6,800,000
Reduced interest rate	100,000
Troubled Debt Restructurings [Member] | Loans With Extended Amortization Terms Or Other Payment Concessions [Member]
Accounts Notes And Loans Receivable [Line Items]
Extended terms and other payment concessions		$ 7,100,000
Troubled Debt Restructurings [Member] | Loans With Other Modifications [Member]
Accounts Notes And Loans Receivable [Line Items]
Other modifications	$ 100,000	$ 500,000
Slower Near-term Growth/Mild Recessionary Scenario S-2 [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance for credit losses probability weighting percentage	75.00%
Description of decline in gross domestic product due to mild recession	As such, the S-2 scenario incorporates a mild recession beginning in the fourth quarter of 2022, spanning three quarters, with a peak-to-trough decline in GDP of about 1.4%.
Downside Scenario S-1 [Member]
Accounts Notes And Loans Receivable [Line Items]
Weighted average percentage of forecast		50.00%
Downside Scenario S-2 [Member]
Accounts Notes And Loans Receivable [Line Items]
Weighted average percentage of forecast		50.00%
Forecast [Member]
Accounts Notes And Loans Receivable [Line Items]
Unemployment percentage rate forecast			4.90%	6.10%	4.00%
Gross domestic product annual growth percentage			2.60%	1.40%	1.60%
Residential Mortgages [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	$ 24,283,000					25,439,000
Loans carried at fair value option	15,100,000					41,000,000.0
Unpaid principal balance	$ 15,300,000					40,100,000
Residential Mortgages [Member] | Troubled Debt Restructurings [Member]
Accounts Notes And Loans Receivable [Line Items]
Number of TDRs subsequently defaulted | Loan	1	1
Recorded Investment	$ 200,000	$ 600,000
Consumer [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	6,523,000					11,887,000
Real estate in process of foreclosure	4,500,000					4,400,000
Real estate acquired through foreclosure	$ 500,000					2,400,000
Consumer [Member] | Troubled Debt Restructurings [Member]
Accounts Notes And Loans Receivable [Line Items]
Number of TDRs subsequently defaulted | Loan	4
Total Commercial And Industrial [Member] | Total Commercial [Member]
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans	$ 6,765,000					11,895,000
Commercial Non-Real Estate [Member]
Accounts Notes And Loans Receivable [Line Items]
Paycheck protection program loans	$ 75,700,000					531,100,000
Commercial Non-Real Estate [Member] | Troubled Debt Restructurings [Member]
Accounts Notes And Loans Receivable [Line Items]
Number of TDRs subsequently defaulted | Loan	3
Recorded Investment	$ 3,100,000
Commercial Non-Real Estate [Member] | Total Commercial And Industrial [Member] | Total Commercial [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans interest bearing rate	1.00%
Loans receivable percentage of origination fee description	These loans also earn an origination fee of 1%, 3%, or 5%, depending on the loan size,
Nonaccrual loans	$ 4,528,000					$ 6,974,000
Commercial Non-Real Estate [Member] | Total Commercial And Industrial [Member] | Minimum [Member] | Total Commercial [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans term	2 years
Loans percentage of origination fee	1.00%
Commercial Non-Real Estate [Member] | Total Commercial And Industrial [Member] | Maximum [Member] | Total Commercial [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans term	5 years
Loans percentage of origination fee	5.00%