Composition of Loan Portfolio (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 746,588		$ 704,531
Total loans	740,900		706,634
Allowance for loan losses	(6,734)	$ (6,419)	(6,095)
Loans, net	$ 740,912		$ 700,539
Percent of loan to total loan portfolio	100.00%		100.00%
Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 2,303		$ 0
Percent of loan to total loan portfolio	0.30%		0.00%
Mortgage loans held for sale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 1,058		$ 2,103
Percent of loan to total loan portfolio	0.10%		0.30%
Commercial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 123,872		$ 106,109
Percent of loan to total loan portfolio	16.60%		15.00%
Mortgage-commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 251,631		$ 238,602
Percent of loan to total loan portfolio	33.70%		33.80%
Mortgage-residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 265,762		$ 256,406
Percent of loan to total loan portfolio	35.50%		36.30%
Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 85,769		$ 84,935
Percent of loan to total loan portfolio	11.50%		12.00%
Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 17,251		$ 18,479
Percent of loan to total loan portfolio	2.30%		2.60%

Loans and Leases Receivable, Net of Deferred Income, Including Loans Held For Sale

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Percentage Of Loan Portfolio

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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.

+ References

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-Number Topic 6

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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 and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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