Loans and Loans Held for Sale - Composition of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Composition of Loans
Portfolio loans, net of unearned income	$ 5,611,419	$ 5,027,612
Loans held for sale	3,793	35,321
Total Loans	5,615,212	5,062,933
Commercial Real Estate
Composition of Loans
Portfolio loans, net of unearned income	2,498,476	2,166,603
Total Loans	2,498,476	2,166,603
Commercial and Industrial
Composition of Loans
Portfolio loans, net of unearned income	1,401,035	1,256,830
Total Loans	1,401,035	1,256,830
Commercial Construction
Composition of Loans
Portfolio loans, net of unearned income	455,884	413,444
Total Loans	455,884	413,444
Residential Mortgage
Composition of Loans
Portfolio loans, net of unearned income	1,190,172	1,116,796
Total Loans	701,982	639,372
Home Equity
Composition of Loans
Total Loans	482,284	470,845
Installment and Other Consumer
Composition of Loans
Total Loans	65,852	73,939
Consumer Construction
Composition of Loans
Total Loans	5,906	6,579
Commercial
Composition of Loans
Portfolio loans, net of unearned income	4,355,395	3,836,877
Commercial \| Commercial Real Estate
Composition of Loans
Portfolio loans, net of unearned income	2,498,476	2,166,603
Commercial \| Commercial and Industrial
Composition of Loans
Portfolio loans, net of unearned income	1,401,035	1,256,830
Commercial \| Commercial Construction
Composition of Loans
Portfolio loans, net of unearned income	455,884	413,444
Consumer
Composition of Loans
Portfolio loans, net of unearned income	1,256,024	1,190,735
Consumer \| Residential Mortgage
Composition of Loans
Portfolio loans, net of unearned income	701,982	639,372
Consumer \| Home Equity
Composition of Loans
Portfolio loans, net of unearned income	482,284	470,845
Consumer \| Installment and Other Consumer
Composition of Loans
Portfolio loans, net of unearned income	65,852	73,939
Consumer \| Consumer Construction
Composition of Loans
Portfolio loans, net of unearned income	$ 5,906	$ 6,579

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.

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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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Amount after allowance and 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. Includes loans held for sale. 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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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