FAIR VALUE MEASUREMENT - Schedule of Inputs Used in Valuing Assets and Liabilities At Fair Value (Details) - Fair Value, Measurements, Nonrecurring - Total $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 302,128
Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.056
Weighted Average Life (Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, term	3 years 9 months 18 days
Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.045
Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.023
Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.352
Performing Loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 105,863
Non-Performing Loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 196,265
Minimum | Performing Loans | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.043
Minimum | Performing Loans | Weighted Average Life (Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, term	4 years 3 months 18 days
Minimum | Performing Loans | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.051
Minimum | Performing Loans | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.009
Minimum | Performing Loans | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.286
Minimum | Non-Performing Loans | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.055
Minimum | Non-Performing Loans | Weighted Average Life (Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, term	3 years 1 month 6 days
Minimum | Non-Performing Loans | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.020
Minimum | Non-Performing Loans | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.029
Minimum | Non-Performing Loans | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.085
Maximum | Performing Loans | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.075
Maximum | Performing Loans | Weighted Average Life (Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, term	9 years
Maximum | Performing Loans | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.099
Maximum | Performing Loans | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.022
Maximum | Performing Loans | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	1.000
Maximum | Non-Performing Loans | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.090
Maximum | Non-Performing Loans | Weighted Average Life (Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, term	4 years 3 months 18 days
Maximum | Non-Performing Loans | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.020
Maximum | Non-Performing Loans | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.029
Maximum | Non-Performing Loans | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.300
Weighted Average | Performing Loans | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.054
Weighted Average | Performing Loans | Weighted Average Life (Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, term	4 years 8 months 12 days
Weighted Average | Performing Loans | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.091
Weighted Average | Performing Loans | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.011
Weighted Average | Performing Loans | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.470
Weighted Average | Non-Performing Loans | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.057
Weighted Average | Non-Performing Loans | Weighted Average Life (Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, term	3 years 4 months 24 days
Weighted Average | Non-Performing Loans | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.020
Weighted Average | Non-Performing Loans | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.029
Weighted Average | Non-Performing Loans | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Financing receivable, measurement input	0.289