FAIR VALUE DISCLOSURES AND REPORTING, THE FAIR VALUE OPTION AND FAIR VALUE MEASUREMENTS - Fair Value of Assets Measured on Nonrecurring Basis (Details) - Fair Value, Measurements, Nonrecurring [Member] - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Impaired loans
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	$ 5,176	$ 15,107
Other real estate owned
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	3,529	5,802
Quoted Prices in Active Markets for Identical Assets (Level 1) | Impaired loans
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Other real estate owned
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	0	0
Significant Other Observable Inputs (Level 2) | Impaired loans
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	0	0
Significant Other Observable Inputs (Level 2) | Other real estate owned
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	0	0
Significant Unobservable Inputs (Level 3) | Impaired loans
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	5,176	15,107
Significant Unobservable Inputs (Level 3) | Other real estate owned
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	$ 3,529	$ 5,802