Loans and Allowance for Credit Losses Summary Of Gross Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	$ 14,984,851	$ 14,718,662
Deferred Revenue	21,674	19,390
Loans, net of unearned income	14,963,177	14,699,272	$ 13,870,701
Real-estate - commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	6,118,533	6,018,582
Loans, net of unearned income	6,118,533	6,018,582	5,558,108
Commercial - industrial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	4,167,809	4,087,486
Loans, net of unearned income	4,167,809	4,087,486	4,035,333
Real-estate - home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	1,595,901	1,625,115
Loans, net of unearned income	1,595,901	1,625,115	1,659,481
Real-estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	1,665,142	1,601,994
Loans, net of unearned income	1,665,142	1,601,994	1,377,459
Real-estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	882,983	843,649
Loans, net of unearned income	882,983	843,649	810,872
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	288,826	291,470
Loans, net of unearned income	288,826	291,470	$ 263,221
Leasing and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	262,315	246,704
Overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	$ 3,342	$ 3,662

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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- Definition

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

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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