Activity in Allowance for Loan Losses (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of period	$ 6,095
Loans charged-off	(367)
Recoveries on loans previously charged-off	50
Net charge-offs	(317)
Provision for Loan Losses	150us-gaap_ProvisionForLoanAndLeaseLosses	358us-gaap_ProvisionForLoanAndLeaseLosses
Balance at end of period	5,928
Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans charged-off	(342)
Recoveries on loans previously charged-off	33
Installment and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans charged-off	(25)
Recoveries on loans previously charged-off	11
Commercial Financial And Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans charged-off	0
Recoveries on loans previously charged-off	$ 6

Allowance for Doubtful Accounts, Charge Offs Net of Recoveries

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

+ Details

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Topic 942

-SubTopic 225

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