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
Purchased
Summary of loans
Gross loans	1,489,137	1,583,028
Unearned income	0	0
Loans, net of unearned income	1,489,137	1,583,028
Commercial, financial, agricultural
Summary of loans
Gross loans	717,490	636,837
Loans, net of unearned income	717,490	636,837
Commercial, financial, agricultural \| Purchased
Summary of loans
Gross loans	128,200	151,430
Loans, net of unearned income	128,200	151,430
Lease financing
Summary of loans
Gross loans	49,250	35,978
Lease financing \| Purchased
Summary of loans
Gross loans	0	0
Real estate – construction
Summary of loans
Gross loans	552,679	357,665
Loans, net of unearned income	552,679	357,665
Real estate – construction \| Purchased
Summary of loans
Gross loans	68,753	65,964
Loans, net of unearned income	68,753	65,964
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 – 1-4 family mortgage \| Purchased
Summary of loans
Gross loans	452,447	531,095
Loans, net of unearned income	452,447	531,095
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
Real estate – commercial mortgage \| Purchased
Summary of loans
Gross loans	823,758	804,680
Loans, net of unearned income	823,758	804,680
Installment loans to individuals
Summary of loans
Gross loans	108,627	115,093
Loans, net of unearned income	155,468	149,908
Installment loans to individuals \| Purchased
Summary of loans
Gross loans	15,979	29,859
Loans, net of unearned income	$ 15,979	$ 29,859

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
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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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.

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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

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-Section 50
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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