MORTGAGE LOANS RECEIVABLE - Past Due Mortgage Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	$ 289,065	$ 51,575
Fair Value	290,180	52,389
Fair Value Over (Under) Unpaid Principal Balance	1,115	814
Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	289,065	51,575
Fair Value	290,180	52,389
Fair Value Over (Under) Unpaid Principal Balance	1,115	814
90+
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	0	0
Fair Value	0	0
Fair Value Over (Under) Unpaid Principal Balance	0	$ 0
Mortgage Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	1,473,894
Fair Value	1,515,762
Fair Value Over (Under) Unpaid Principal Balance	41,868
Mortgage Loans Receivable | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	1,473,894
Fair Value	1,515,762
Fair Value Over (Under) Unpaid Principal Balance	41,868
Mortgage Loans Receivable | 90+
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	0
Fair Value	0
Fair Value Over (Under) Unpaid Principal Balance	$ 0