Non Purchased Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Summary of loans
Gross loans	$ 6,205,118	$ 5,414,625
Unearned income	(2,409)	(1,163)
Loans, net of unearned income	6,202,709	5,413,462
Commercial, financial, agricultural
Summary of loans
Gross loans	717,490	636,837
Loans, net of unearned income	717,490	636,837
Lease financing
Summary of loans
Gross loans	49,250	35,978
Real estate – construction
Summary of loans
Gross loans	552,679	357,665
Loans, net of unearned income	552,679	357,665
Real estate – 1-4 family mortgage
Summary of loans
Gross loans	1,878,177	1,735,323
Loans, net of unearned income	1,878,177	1,735,323
Real estate – commercial mortgage
Summary of loans
Gross loans	2,898,895	2,533,729
Loans, net of unearned income	2,898,895	2,533,729
Installment loans to individuals
Summary of loans
Gross loans	108,627	115,093
Loans, net of unearned income	155,468	149,908
Non-Purchased
Summary of loans
Gross loans	4,715,981	3,831,597
Unearned income	(2,409)	(1,163)
Loans, net of unearned income	4,713,572	3,830,434
Non-Purchased \| Commercial, financial, agricultural
Summary of loans
Gross loans	589,290	485,407
Non-Purchased \| Lease financing
Summary of loans
Gross loans	49,250	35,978
Non-Purchased \| Real estate – construction
Summary of loans
Gross loans	483,926	291,701
Non-Purchased \| Real estate – 1-4 family mortgage
Summary of loans
Gross loans	1,425,730	1,204,228
Non-Purchased \| Real estate – commercial mortgage
Summary of loans
Gross loans	2,075,137	1,729,049
Non-Purchased \| Installment loans to individuals
Summary of loans
Gross loans	$ 92,648	$ 85,234

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=65890831&loc=d3e10152-111534

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

Reference 3: 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)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
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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
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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