|**Loans (Past Due Status) (Details) (USD $)In Thousands, unless otherwise specified** | Mar. 31, 2013                                          | Dec. 31, 2012                                         
|------------------------------------------------------------------------------------- | ------------------------------------------------------ | ------------------------------------------------------
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | $ 10,049                                               | $ 11,443                                              
|60 - 89 days past due                                                                 | 3,246                                                  | 5,795                                                 
|More than 90 days past due                                                            | 20,453                                                 | 24,060                                                
|Nonaccrual                                                                            | 70,503                                                 | 79,242                                                
|Total past due and nonaccrual                                                         | 104,251                                                | 120,540                                               
|Current and accruing                                                                  | 1,009,514                                              | 1,056,495                                             
|Loans held for investment                                                             | 1,113,765                                              | 1,177,035                                             
|Commercial and agricultural [Member]                                                  |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|Loans held for investment                                                             | 77,490                                                 | 79,704                                                
|Real estate - construction [Member]                                                   |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|Loans held for investment                                                             | 57,653                                                 | 58,414                                                
|Real estate - mortgage, 1-4 family residential [Member]                               |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|Loans held for investment                                                             | 520,808                                                | 553,538                                               
|Real estate - mortgage, commercial [Member]                                           |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|Loans held for investment                                                             | 414,995                                                | 441,836                                               
|Consumer [Member]                                                                     |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|Loans held for investment                                                             | 42,819                                                 | 43,543                                                
|PC [Member]                                                                           |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 4,258                                                  | 7,355                                                 
|60 - 89 days past due                                                                 | 242                                                    | 999                                                   
|More than 90 days past due                                                            | 55                                                     | 227                                                   
|Nonaccrual                                                                            | 70,503                                                 | 79,242                                                
|Total past due and nonaccrual                                                         | 75,058                                                 | 87,823                                                
|Current and accruing                                                                  | 832,823                                                | 860,820                                               
|Loans held for investment                                                             | 907,881                                                | 948,643                                               
|PC [Member] | Commercial and agricultural [Member]                                    |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 30                                                     | 515                                                   
|60 - 89 days past due                                                                 | 1                                                      | 0                                                     
|More than 90 days past due                                                            | 0                                                      | 50                                                    
|Nonaccrual                                                                            | 2,350                                                  | 2,746                                                 
|Total past due and nonaccrual                                                         | 2,381                                                  | 3,311                                                 
|Current and accruing                                                                  | 62,200                                                 | 61,727                                                
|Loans held for investment                                                             | 64,581                                                 | 65,038                                                
|PC [Member] | Real estate - construction [Member]                                     |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 367                                                    | 26                                                    
|60 - 89 days past due                                                                 | 0                                                      | 119                                                   
|More than 90 days past due                                                            | 0                                                      | 0                                                     
|Nonaccrual                                                                            | 11,762                                                 | 14,297                                                
|Total past due and nonaccrual                                                         | 12,129                                                 | 14,442                                                
|Current and accruing                                                                  | 43,191                                                 | 41,290                                                
|Loans held for investment                                                             | 55,320                                                 | 55,732                                                
|PC [Member] | Real estate - mortgage, 1-4 family residential [Member]                 |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 2,722                                                  | 6,173                                                 
|60 - 89 days past due                                                                 | 82                                                     | 880                                                   
|More than 90 days past due                                                            | 55                                                     | 0                                                     
|Nonaccrual                                                                            | 19,111                                                 | 18,372                                                
|Total past due and nonaccrual                                                         | 21,970                                                 | 25,425                                                
|Current and accruing                                                                  | 462,224                                                | 488,898                                               
|Loans held for investment                                                             | 484,194                                                | 514,323                                               
|PC [Member] | Real estate - mortgage, commercial [Member]                             |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 931                                                    | 617                                                   
|60 - 89 days past due                                                                 | 147                                                    | 0                                                     
|More than 90 days past due                                                            | 0                                                      | 177                                                   
|Nonaccrual                                                                            | 37,217                                                 | 43,621                                                
|Total past due and nonaccrual                                                         | 38,295                                                 | 44,415                                                
|Current and accruing                                                                  | 224,247                                                | 226,948                                               
|Loans held for investment                                                             | 262,542                                                | 271,363                                               
|PC [Member] | Consumer [Member]                                                       |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 208                                                    | 24                                                    
|60 - 89 days past due                                                                 | 12                                                     | 0                                                     
|More than 90 days past due                                                            | 0                                                      | 0                                                     
|Nonaccrual                                                                            | 63                                                     | 206                                                   
|Total past due and nonaccrual                                                         | 283                                                    | 230                                                   
|Current and accruing                                                                  | 40,961                                                 | 41,957                                                
|Loans held for investment                                                             | 41,244                                                 | 42,187                                                
|PI [Member]                                                                           |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 5,791                                                  | 4,088                                                 
|60 - 89 days past due                                                                 | 3,004                                                  | 4,796                                                 
|More than 90 days past due                                                            | 20,398                                                 | 23,833                                                
|Nonaccrual                                                                            | 0                                                      | 0                                                     
|Total past due and nonaccrual                                                         | 29,193                                                 | 32,717                                                
|Current and accruing                                                                  | 176,691                                                | 195,675                                               
|Loans held for investment                                                             | 205,884                                                | 228,392                                               
|PI [Member] | Commercial and agricultural [Member]                                    |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 1,056                                                  | 100                                                   
|60 - 89 days past due                                                                 | 60                                                     | 1                                                     
|More than 90 days past due                                                            | 811                                                    | 1,103                                                 
|Nonaccrual                                                                            | 0                                                      | 0                                                     
|Total past due and nonaccrual                                                         | 1,927                                                  | 1,204                                                 
|Current and accruing                                                                  | 10,982                                                 | 13,462                                                
|Loans held for investment                                                             | 12,909                                                 | 14,666                                                
|PI [Member] | Real estate - construction [Member]                                     |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 0                                                      | 117                                                   
|60 - 89 days past due                                                                 | 48                                                     | 0                                                     
|More than 90 days past due                                                            | 523                                                    | 655                                                   
|Nonaccrual                                                                            | 0                                                      | 0                                                     
|Total past due and nonaccrual                                                         | 571                                                    | 772                                                   
|Current and accruing                                                                  | 1,761                                                  | 1,910                                                 
|Loans held for investment                                                             | 2,332                                                  | 2,682                                                 
|PI [Member] | Real estate - mortgage, 1-4 family residential [Member]                 |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 896                                                    | 1,308                                                 
|60 - 89 days past due                                                                 | 0                                                      | 495                                                   
|More than 90 days past due                                                            | 3,530                                                  | 4,678                                                 
|Nonaccrual                                                                            | 0                                                      | 0                                                     
|Total past due and nonaccrual                                                         | 4,426                                                  | 6,481                                                 
|Current and accruing                                                                  | 32,481                                                 | 32,734                                                
|Loans held for investment                                                             | 36,907                                                 | 39,215                                                
|PI [Member] | Real estate - mortgage, commercial [Member]                             |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 3,836                                                  | 2,559                                                 
|60 - 89 days past due                                                                 | 2,896                                                  | 4,300                                                 
|More than 90 days past due                                                            | 15,533                                                 | 17,384                                                
|Nonaccrual                                                                            | 0                                                      | 0                                                     
|Total past due and nonaccrual                                                         | 22,265                                                 | 24,243                                                
|Current and accruing                                                                  | 130,168                                                | 146,230                                               
|Loans held for investment                                                             | 152,433                                                | 170,473                                               
|PI [Member] | Consumer [Member]                                                       |                                                        |                                                       
|**Financing Receivable, Recorded Investment, Past Due [Line Items]**                  |                                                        |                                                       
|30 - 59 days past due                                                                 | 3                                                      | 4                                                     
|60 - 89 days past due                                                                 | 0                                                      | 0                                                     
|More than 90 days past due                                                            | 1                                                      | 13                                                    
|Nonaccrual                                                                            | 0                                                      | 0                                                     
|Total past due and nonaccrual                                                         | 4                                                      | 17                                                    
|Current and accruing                                                                  | 1,299                                                  | 1,339                                                 
|Loans held for investment                                                             | $ 1,303                                                | $ 1,356                                               
|                                                                                     
|[1]
              Derived from audited consolidated financial statements              | [1]                                                    | Derived from audited consolidated financial statements
|[1]                                                                                   | Derived from audited consolidated financial statements

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