Loans and Allowance for Credit Losses Summary Of Gross Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	$ 16,395,670	$ 16,192,439
Unearned income	(27,212)	(26,639)
Loans and leases, net of unearned income	16,368,458	16,165,800	$ 15,792,969
Real-estate - commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	6,497,973	6,434,285
Loans and leases, net of unearned income	6,497,973	6,434,285	6,304,475
Commercial - industrial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	4,365,248	4,404,548
Loans and leases, net of unearned income	4,365,248	4,404,548	4,264,602
Real estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	2,451,966	2,251,044
Loans and leases, net of unearned income	2,451,966	2,251,044	2,094,530
Real-estate - home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	1,386,974	1,452,137
Loans and leases, net of unearned income	1,386,974	1,452,137	1,491,395
Real estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	922,547	916,599
Loans and leases, net of unearned income	922,547	916,599	990,705
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	452,874	419,186
Loans and leases, net of unearned income	452,874	419,186	$ 360,315
Equipment lease financing and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	314,901	311,866
Overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, gross of unearned income	$ 3,187	$ 2,774

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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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