FAIR VALUES MEASUREMENTS (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Assets:
Cash and cash equivalents	$ 138,648		$ 122,564
Escrow deposits and restricted cash	71,699		48,181
Non-mortgage loans receivable, net	24,500		24,338
Liabilities:
Senior notes payable and other debt, gross	13,438,942		12,361,244
Real estate received in settlement of loan receivable	1,566,395	$ 0
Capital expenditures	31,800
Non-mortgage loans receivable, net
Assets:
Non-mortgage loans receivable, net	24,500		24,338
Non-mortgage loans receivable, fair value	23,626		23,416
Secured/mortgage loans and other, net
Assets:
Secured mortgage loans and other, net	27,749		513,669
Debt securities, held-to-maturity, fair value	$ 27,790		493,627
Government-sponsored pooled loan investments, net
Assets:
Government-sponsored pooled loan investments, net			43,406
Mezzanine Loan | Minimum | Fair Value, Inputs, Level 3 | Direct Cap Approach
Liabilities:
Fair value measurement input, percentage	0.068
Mezzanine Loan | Maximum | Fair Value, Inputs, Level 3 | Direct Cap Approach
Liabilities:
Fair value measurement input, percentage	0.067
Mezzanine Loan | Weighted Average | Fair Value, Inputs, Level 3 | Market Approach
Liabilities:
Fair value measurement input, amount	$ 88
Carrying Amount
Assets:
Cash and cash equivalents	138,648		122,564
Escrow deposits and restricted cash	71,699		48,181
Derivative instruments	44,005		24,316
Liabilities:
Derivative instruments	317		145
Redeemable Noncontrolling Interest, Equity, Carrying Amount	166,894		162,663
Carrying Amount | Brookdale Senior Living
Assets:
Stock warrants	40,451		23,621
Carrying Amount | Non-mortgage loans receivable, net
Assets:
Non-mortgage loans receivable, net	24,500		24,338
Carrying Amount | Secured/mortgage loans and other, net
Assets:
Secured mortgage loans and other, net	27,749		493,669
Carrying Amount | Government-sponsored pooled loan investments, net
Assets:
Government-sponsored pooled loan investments, net	0		43,406
Fair Value
Assets:
Cash and cash equivalents, fair value	138,648		122,564
Escrow deposits and restricted cash	71,699		48,181
Derivative instruments	44,005		24,316
Liabilities:
Long-term debt and short-term borrowings, fair value	12,633,140		11,493,824
Derivative instruments	317		145
Redeemable OP Units, fair value	166,894		162,663
Fair Value | Brookdale Senior Living
Assets:
Stock warrants	40,451		23,621
Fair Value | Non-mortgage loans receivable, net
Assets:
Non-mortgage loans receivable, fair value	23,626		23,416
Fair Value | Secured/mortgage loans and other, net
Assets:
Debt securities, held-to-maturity, fair value	27,790		493,627
Fair Value | Government-sponsored pooled loan investments, net
Assets:
Government-sponsored pooled loan investments, net	$ 0		$ 43,406