FAIR VALUE MEASUREMENT - Schedule of Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Purchase options related to real estate loans	$ 2,800	$ 7,161
Liabilities:
Interest rate swaps	15,723	30,850
Recurring basis
Assets:
Purchase options related to real estate loans	2,800	7,161
Recurring basis | Interest rate swaps
Liabilities:
Interest rate swaps	15,723	30,850
Recurring basis | Level 1
Assets:
Purchase options related to real estate loans	0	0
Recurring basis | Level 1 | Interest rate swaps
Liabilities:
Interest rate swaps	0	0
Recurring basis | Level 2
Assets:
Purchase options related to real estate loans	0	0
Recurring basis | Level 2 | Interest rate swaps
Liabilities:
Interest rate swaps	15,723	30,850
Recurring basis | Level 3
Assets:
Purchase options related to real estate loans	2,800	7,161
Recurring basis | Level 3 | Interest rate swaps
Liabilities:
Interest rate swaps	$ 0	$ 0