LOAN CREDIT QUALITY AND RELATED ALLOWANCE FOR LOAN LOSSES - Loan Modifications Considered TDRs (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2016
USD ($)
contract
Dec. 31, 2015
USD ($)
contract
Troubled debt restructurings    
Number of Contracts | contract 4 22
Pre-Modification Outstanding Recorded Investment $ 797 $ 2,586
Post-Modification Outstanding Recorded Investment $ 797 $ 2,586
Number of loan modifications, subsequently defaulted | contract 0 8,000
Recorded investment, subsequently defaulted $ 0 $ 722
Commercial, Financial, and Agricultural    
Troubled debt restructurings    
Number of Contracts | contract 0 4
Pre-Modification Outstanding Recorded Investment $ 0 $ 213
Post-Modification Outstanding Recorded Investment $ 0 $ 213
Number of loan modifications, subsequently defaulted | contract 0 1,000
Recorded investment, subsequently defaulted $ 0 $ 106
Residential Real Estate Mortgage    
Troubled debt restructurings    
Number of Contracts | contract 3 11
Pre-Modification Outstanding Recorded Investment $ 397 $ 962
Post-Modification Outstanding Recorded Investment $ 397 $ 962
Number of loan modifications, subsequently defaulted | contract 0 6,000
Recorded investment, subsequently defaulted $ 0 $ 374
Commercial Real Estate Mortgage    
Troubled debt restructurings    
Number of Contracts | contract 1 6
Pre-Modification Outstanding Recorded Investment $ 400 $ 1,013
Post-Modification Outstanding Recorded Investment $ 400 $ 1,013
Number of loan modifications, subsequently defaulted | contract 0 1,000
Recorded investment, subsequently defaulted $ 0 $ 242
Construction Real Estate Mortgage    
Troubled debt restructurings    
Number of Contracts | contract 0 1
Pre-Modification Outstanding Recorded Investment $ 0 $ 398
Post-Modification Outstanding Recorded Investment $ 0 $ 398