CONCENTRATION OF CREDIT RISK - Triple-Net Leased Properties (Details) - Customer Concentration Risk	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenues \| Brookdale Senior Living
Concentration Risk
Concentration percentage	4.60%	4.80%
Revenues \| Ardent
Concentration Risk
Concentration percentage	3.00%	3.10%
Revenues \| Kindred
Concentration Risk
Concentration percentage	3.20%	3.40%
NOI \| Brookdale Senior Living
Concentration Risk
Concentration percentage	8.80%	8.80%
NOI \| Ardent
Concentration Risk
Concentration percentage	5.80%	5.70%
NOI \| Kindred
Concentration Risk
Concentration percentage	6.20%	6.20%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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