Loans and Loans Held for Sale - Composition of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Composition of Loans
Portfolio loans, net of unearned income	$ 5,761,449	$ 5,611,419
Loans held for sale	4,485	3,793
Total Loans	5,765,934	5,615,212
Commercial real estate
Composition of Loans
Portfolio loans, net of unearned income	2,685,994	2,498,476
Total Loans	2,685,994	2,498,476
Commercial and industrial
Composition of Loans
Portfolio loans, net of unearned income	1,433,266	1,401,035
Total Loans	1,433,266	1,401,035
Commercial construction
Composition of Loans
Portfolio loans, net of unearned income	384,334	455,884
Total Loans	384,334	455,884
Residential mortgage
Composition of Loans
Total Loans	698,774	701,982
Home equity
Composition of Loans
Total Loans	487,326	482,284
Installment and other consumer
Composition of Loans
Total Loans	67,204	65,852
Consumer construction
Composition of Loans
Total Loans	4,551	5,906
Commercial
Composition of Loans
Portfolio loans, net of unearned income	4,503,594	4,355,395
Commercial \| Commercial real estate
Composition of Loans
Portfolio loans, net of unearned income	2,685,994	2,498,476
Commercial \| Commercial and industrial
Composition of Loans
Portfolio loans, net of unearned income	1,433,266	1,401,035
Commercial \| Commercial construction
Composition of Loans
Portfolio loans, net of unearned income	384,334	455,884
Consumer
Composition of Loans
Portfolio loans, net of unearned income	1,257,855	1,256,024
Consumer \| Residential mortgage
Composition of Loans
Portfolio loans, net of unearned income	698,774	701,982
Consumer \| Home equity
Composition of Loans
Portfolio loans, net of unearned income	487,326	482,284
Consumer \| Installment and other consumer
Composition of Loans
Portfolio loans, net of unearned income	67,204	65,852
Consumer \| Consumer construction
Composition of Loans
Portfolio loans, net of unearned income	$ 4,551	$ 5,906

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=82891408&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=84173941&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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