Loans (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Summary of loans, by loan type
Total loans	$ 5,052,161	$ 4,775,004
Commercial, financial and agricultural
Summary of loans, by loan type
Total loans	2,841,022	2,525,380
Real estate - mortgage
Summary of loans, by loan type
Total loans	837,326	838,467
Real estate - construction
Summary of loans, by loan type
Total loans	1,119,342	1,147,669
Consumer
Summary of loans, by loan type
Total loans	67,422	74,514
Foreign
Summary of loans, by loan type
Total loans	$ 187,049	$ 188,974

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 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524

Reference 2: 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=28367877&loc=d3e4428-111522

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