Loans and Allowance for Credit Losses Summary Of Gross Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 19,052,377	$ 16,864,336
Unearned income	(23,756)	(26,810)
Net Loans	19,028,621	16,837,526
Real estate - commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	7,046,330	6,700,776
Net Loans	7,046,330	6,700,776
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	5,968,154	4,446,701
Net Loans	5,968,154	4,446,701
Real estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	3,061,835	2,641,465
Net Loans	3,061,835	2,641,465
Real-estate - home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,222,709	1,314,944
Net Loans	1,222,709	1,314,944
Real-estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,007,534	971,079
Net Loans	1,007,534	971,079
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	469,551	463,164
Net Loans	469,551	463,164
Equipment lease financing and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	274,570	322,625
Overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 1,694	$ 3,582

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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