Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Summary of loans, by loan type
Total loans	$ 6,202,264	$ 5,964,688
Commercial, financial and agricultural
Summary of loans, by loan type
Total loans	3,172,260	2,993,203
Real estate - mortgage
Summary of loans, by loan type
Total loans	1,108,371	1,032,222
Commercial Real Estate: Other Construction and Land Development
Summary of loans, by loan type
Total loans	1,704,804	1,716,875
Consumer
Summary of loans, by loan type
Total loans	53,959	55,168
Foreign
Summary of loans, by loan type
Total loans	$ 162,870	$ 167,220

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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