Loans and the Allowance for Loan Losses - (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Summary of loans
Gross loans	$ 5,967,302	$ 5,414,625
Unearned income	(1,873)	(1,163)
Loans, net of unearned income	5,965,429	5,413,462
Allowance for loan losses	(44,098)	(42,437)
Loans, net	5,921,331	5,371,025
Commercial, financial, agricultural
Summary of loans
Gross loans	682,936	636,837
Lease financing
Summary of loans
Gross loans	44,989	35,978
Real estate – construction
Summary of loans
Gross loans	452,731	357,665
Real estate – 1-4 family mortgage
Summary of loans
Gross loans	1,849,046	1,735,323
Real estate – commercial mortgage
Summary of loans
Gross loans	2,823,676	2,533,729
Installment loans to individuals
Summary of loans
Gross loans	$ 113,924	$ 115,093

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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.

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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.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums over and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans and leases covered under loss sharing agreements.

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