Loans - Summary of Allowance for Loan Losses (Detail) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance, beginning of year $ 9,119 $ 10,020 $ 10,343
Provisions charged to operating expense 978   125
Loans charged off (1,088) (1,589) (2,114)
Recoveries 793 688 1,666
Balance, end of year 9,802 9,119 10,020
Ending balance, individually evaluated for impairment 873    
Ending balance, collectively evaluated for impairment 8,929 9,119 10,020
Loans:      
Individually evaluated for impairment 3,881 3,371 244
Collectively evaluated for impairment 876,192 579,178 441,730
Acquired loans with deteriorated credit quality 9,077    
Receivables Factoring [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Provisions charged to operating expense 978    
Loans charged off (656)    
Recoveries 633    
Balance, end of year 955    
Ending balance, individually evaluated for impairment 473    
Ending balance, collectively evaluated for impairment 482    
Loans:      
Individually evaluated for impairment 1,605    
Collectively evaluated for impairment 80,995    
Commercial, Financial, and Agricultural [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance, beginning of year 1,398 1,158 1,423
Provisions charged to operating expense 61 (47) (435)
Loans charged off (3) (32) (41)
Recoveries 67 319 211
Balance, end of year 1,523 1,398 1,158
Ending balance, collectively evaluated for impairment 1,523 1,398 1,158
Loans:      
Individually evaluated for impairment   27  
Collectively evaluated for impairment 130,656 114,978 92,147
Acquired loans with deteriorated credit quality 1,001    
Real Estate - Mortgage [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance, beginning of year 4,449 5,094 5,509
Provisions charged to operating expense 988 864 (397)
Loans charged off (429) (1,557) (409)
Recoveries 39 49 391
Balance, end of year 5,047 4,449 5,094
Ending balance, individually evaluated for impairment 350    
Ending balance, collectively evaluated for impairment 4,697 4,449 5,094
Loans:      
Individually evaluated for impairment 2,078 3,344 244
Collectively evaluated for impairment 568,363 399,709 302,873
Acquired loans with deteriorated credit quality 6,827    
Real Estate - Construction [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance, beginning of year 964 497 1,071
Provisions charged to operating expense (350) 162 (303)
Loans charged off     (1,292)
Recoveries 33 305 1,021
Balance, end of year 647 964 497
Ending balance, individually evaluated for impairment 50    
Ending balance, collectively evaluated for impairment 597 964 497
Loans:      
Individually evaluated for impairment 198    
Collectively evaluated for impairment 82,551 58,372 36,267
Acquired loans with deteriorated credit quality 914    
Consumer [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance, beginning of year 243 169 90
Provisions charged to operating expense 298 58 408
Loans charged off     (372)
Recoveries 21 15 43
Balance, end of year 562 243 169
Ending balance, collectively evaluated for impairment 562 243 169
Loans:      
Collectively evaluated for impairment 13,627 6,113 10,030
Acquired loans with deteriorated credit quality 335    
Leases [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance, beginning of year   4 29
Provisions charged to operating expense   (3) (25)
Balance, end of year     4
Ending balance, collectively evaluated for impairment     4
Loans:      
Collectively evaluated for impairment   6 413
Unallocated [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance, beginning of year 2,065 3,098 2,221
Provisions charged to operating expense (997) (1,034) 877
Balance, end of year 1,068 2,065 3,098
Ending balance, collectively evaluated for impairment $ 1,068 $ 2,065 $ 3,098