FAIR VALUE ACCOUNTING - Level 3 Fair Value Inputs (Details) - Fair Value, Inputs, Level 3 $ in Thousands	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Foreclosed and repossessed assets, net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of loans receivable	$ 734	$ 1,460
Foreclosed and repossessed assets, net | Estimated costs to sell | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed and repossessed assets, impaired loans, measurement input	0.10	0.10
Foreclosed and repossessed assets, net | Estimated costs to sell | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed and repossessed assets, impaired loans, measurement input	0.15	0.15
Impaired loans with allocated allowances
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of loans receivable	$ 4,058	$ 3,175
Impaired loans with allocated allowances | Estimated costs to sell | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed and repossessed assets, impaired loans, measurement input	0.10	0.10
Impaired loans with allocated allowances | Estimated costs to sell | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed and repossessed assets, impaired loans, measurement input	0.15	0.15
Mortgage servicing rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of MSR asset; end of period	$ 3,509	$ 4,309
Mortgage servicing rights | Discounted rates | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing asset, measurement input	0.095	0.095
Mortgage servicing rights | Discounted rates | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing asset, measurement input	0.125	0.125