Loans and Allowance for Loan Losses, Broken Down by Portfolio Segment (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
Loans
Individually evaluated	$ 4,351		$ 4,387
Collectively evaluated	566,763		403,725
Total	571,114		408,112
Allowance for Loan Losses
Individually evaluated	748		1,103
Collectively evaluated	4,924		3,624
Total	5,672	5,393	4,727
Real Estate
Loans
Individually evaluated	4,218		4,111
Collectively evaluated	468,851		333,299
Total	473,069		337,410
Allowance for Loan Losses
Individually evaluated	680		917
Collectively evaluated	3,897		3,231
Total	4,577		4,148
Installment and Other
Loans
Individually evaluated	41		55
Collectively evaluated	19,698		16,401
Total	19,739		16,456
Allowance for Loan Losses
Individually evaluated	36		110
Collectively evaluated	555		49
Total	591		159
Commercial Financial And Agricultural
Loans
Individually evaluated	92		221
Collectively evaluated	78,214		54,025
Total	78,306		54,246
Allowance for Loan Losses
Individually evaluated	32		76
Collectively evaluated	472		344
Total	$ 504		$ 420

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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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.

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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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