Loans (Modified Loans by Type of Modification) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	$ 18,824,251	$ 17,154,969
Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0	1,051
Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	33,251	0
Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	2,092	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0	1,051	$ 2,189
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	33,251	0	1,556
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0	0	0
Charge-offs | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		371	4,278
Charge-offs | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		352	0
Charge-offs | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		0	0
Proceeds from sales | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		0
Proceeds from sales | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		1,070
Proceeds from sales | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		0
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	5,959,133	5,674,798
Commercial Portfolio Segment [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0
Commercial Portfolio Segment [Member] | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	13,813
Commercial Portfolio Segment [Member] | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0
Commercial Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0		1,162
Commercial Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	13,813		0
Commercial Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0		0
Commercial Real Estate, Buildings, Land and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	7,301,920	6,706,078
Commercial Real Estate, Buildings, Land and Other [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0	1,051
Commercial Real Estate, Buildings, Land and Other [Member] | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	19,438	0
Commercial Real Estate, Buildings, Land and Other [Member] | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	2,092	0
Commercial Real Estate, Buildings, Land and Other [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0	1,051	306
Commercial Real Estate, Buildings, Land and Other [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	19,438	0	1,556
Commercial Real Estate, Buildings, Land and Other [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	0	0	0
Commercial Real Estate, Buildings, Land and Other [Member] | Charge-offs | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		371
Commercial Real Estate, Buildings, Land and Other [Member] | Charge-offs | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		352
Commercial Real Estate, Buildings, Land and Other [Member] | Charge-offs | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		0
Commercial Real Estate, Buildings, Land and Other [Member] | Proceeds from sales | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		0
Commercial Real Estate, Buildings, Land and Other [Member] | Proceeds from sales | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		1,070
Commercial Real Estate, Buildings, Land and Other [Member] | Proceeds from sales | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts		0
Commercial and Industrial Total Energy Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts	$ 935,265	$ 925,729
Commercial and Industrial Total Energy Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts			721
Commercial and Industrial Total Energy Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts			0
Commercial and Industrial Total Energy Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts			0
Commercial and Industrial Total Energy Loans [Member] | Charge-offs | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts			4,278
Commercial and Industrial Total Energy Loans [Member] | Charge-offs | Combination: Payment Delay and Term Extention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts			0
Commercial and Industrial Total Energy Loans [Member] | Charge-offs | Extended Maturity and Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned discounts			$ 0