Loans and Allowance for Loan Losses - Summary of Trouble Debt Restructuring by Loan Class of Covered Loans (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Modifications [Line Items]
Troubled debt restructuring loans	$ 20,900	$ 23,900
Covered Loans [Member] | Accruing Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	100	62
Troubled debt restructuring loans	22,243	17,090
Covered Loans [Member] | Accruing Loans [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	1	1
Troubled debt restructuring loans	13	37
Covered Loans [Member] | Accruing Loans [Member] | Real Estate - Construction and Development [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	3	6
Troubled debt restructuring loans	3,256	2,921
Covered Loans [Member] | Accruing Loans [Member] | Real Estate - Commercial and Farmland [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	13	9
Troubled debt restructuring loans	7,255	6,469
Covered Loans [Member] | Accruing Loans [Member] | Real Estate - Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	83	46
Troubled debt restructuring loans	11,719	7,663
Covered Loans [Member] | Accruing Loans [Member] | Consumer Installment Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts
Troubled debt restructuring loans
Covered Loans [Member] | Non-Accruing Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	24	21
Troubled debt restructuring loans	5,021	10,272
Covered Loans [Member] | Non-Accruing Loans [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	5	1
Troubled debt restructuring loans	71
Covered Loans [Member] | Non-Accruing Loans [Member] | Real Estate - Construction and Development [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	4	4
Troubled debt restructuring loans	52	806
Covered Loans [Member] | Non-Accruing Loans [Member] | Real Estate - Commercial and Farmland [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	5	8
Troubled debt restructuring loans	3,946	7,574
Covered Loans [Member] | Non-Accruing Loans [Member] | Real Estate - Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	8	8
Troubled debt restructuring loans	942	1,892
Covered Loans [Member] | Non-Accruing Loans [Member] | Consumer Installment Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	2
Troubled debt restructuring loans	$ 10