Purchased Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Summary of loans
Gross loans	$ 6,374,288	$ 6,205,118
Unearned income	(3,281)	(2,409)
Loans, net of unearned income	6,371,007	6,202,709
Purchased loans
Summary of loans
Gross loans	1,312,109	1,489,137
Unearned income	0	0
Loans, net of unearned income	1,312,109	1,489,137
Commercial, financial, agricultural
Summary of loans
Gross loans	760,582	717,490
Loans, net of unearned income	760,582	717,490
Commercial, financial, agricultural \| Purchased loans
Summary of loans
Gross loans	102,869	128,200
Real estate – construction
Summary of loans
Gross loans	460,807	552,679
Loans, net of unearned income	460,807	552,679
Real estate – construction \| Purchased loans
Summary of loans
Gross loans	35,946	68,753
Real estate – 1-4 family mortgage
Summary of loans
Gross loans	1,952,394	1,878,177
Loans, net of unearned income	1,952,394	1,878,177
Real estate – 1-4 family mortgage \| Purchased loans
Summary of loans
Gross loans	400,460	452,447
Real estate – commercial mortgage
Summary of loans
Gross loans	3,040,963	2,898,895
Loans, net of unearned income	3,040,963	2,898,895
Real estate – commercial mortgage \| Purchased loans
Summary of loans
Gross loans	759,743	823,758
Installment loans to individuals
Summary of loans
Gross loans	107,195	108,627
Loans, net of unearned income	156,261	155,468
Installment loans to individuals \| Purchased loans
Summary of loans
Gross loans	$ 13,091	$ 15,979

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=84159169&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=84173941&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)
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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
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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