FAIR VALUES OF FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets:
Cash and cash equivalents	$ 149,599	$ 149,725
Escrow deposits and restricted cash	49,848	46,872
Non-mortgage loans receivable, net	24,116	19,024
Liabilities:
Senior notes payable and other debt, gross	12,477,876	12,093,138
Redeemable OP Units, fair value	217,200	182,100
Non-mortgage loans receivable, net
Assets:
Non-mortgage loans receivable, net	24,116	19,024
Non-mortgage loans receivable, fair value	23,826	19,039
Secured/mortgage loans and other, net
Assets:
Secured mortgage loans and other, net	488,827	488,913
Debt securities, held-to-maturity, fair value	483,491	478,931
Government-sponsored pooled loan investments, net
Assets:
Government-sponsored pooled loan investments, net	41,561	41,213
Carrying Amount
Assets:
Cash and cash equivalents	149,599	149,725
Escrow deposits and restricted cash	49,848	46,872
Derivative instruments	10,410	1,128
Liabilities:
Derivative instruments	2,571	12,290
OP Units	217,225	182,112
Carrying Amount | Brookdale Senior Living
Assets:
Stock warrants	77,452	48,884
Carrying Amount | Non-mortgage loans receivable, net
Assets:
Non-mortgage loans receivable, net	24,116	19,024
Carrying Amount | Secured/mortgage loans and other, net
Assets:
Secured mortgage loans and other, net	488,827	488,913
Carrying Amount | Government-sponsored pooled loan investments, net
Assets:
Government-sponsored pooled loan investments, net	41,561	41,213
Fair Value
Assets:
Cash and cash equivalents, fair value	149,599	149,725
Escrow deposits and restricted cash	49,848	46,872
Derivative instruments	10,410	1,128
Liabilities:
Long-term debt and short-term borrowings, fair value	12,518,899	12,891,937
Derivative instruments	2,571	12,290
Redeemable OP Units, fair value	217,225	182,112
Fair Value | Brookdale Senior Living
Assets:
Stock warrants	77,452	48,884
Fair Value | Non-mortgage loans receivable, net
Assets:
Non-mortgage loans receivable, fair value	23,826	19,039
Fair Value | Secured/mortgage loans and other, net
Assets:
Debt securities, held-to-maturity, fair value	483,491	478,931
Fair Value | Government-sponsored pooled loan investments, net
Assets:
Government-sponsored pooled loan investments, net	$ 41,561	$ 41,213