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
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Concentration of Credit Risk - Schedule of Concentration Risk (Details) - Brookdale	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Total Assets
Concentration Risk [Line Items]
Concentration risk (as a percent)			6.00%		6.00%
Revenue
Concentration Risk [Line Items]
Concentration risk (as a percent)	4.00%	6.00%	4.00%	6.00%
Senior housing triple-net \| Total Assets
Concentration Risk [Line Items]
Concentration risk (as a percent)			40.00%		27.00%
Senior housing triple-net \| Revenue
Concentration Risk [Line Items]
Concentration risk (as a percent)	38.00%	41.00%	35.00%	42.00%