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
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Concentration of Credit Risk - Schedule of Concentration Risk (Details)	1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	Apr. 30, 2018 facility	Mar. 31, 2017 property	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Total Assets \| Brookdale
Concentration Risk [Line Items]
Concentration risk (as a percent)					8.00%		10.00%
Revenue \| Brookdale
Concentration Risk [Line Items]
Concentration risk (as a percent)			6.00%	8.00%	6.00%	10.00%
Senior housing triple-net
Concentration Risk [Line Items]
Number of properties disposed	2	64
Senior housing triple-net \| Total Assets \| Brookdale
Concentration Risk [Line Items]
Concentration risk (as a percent)					36.00%		39.00%
Senior housing triple-net \| Revenue \| Brookdale
Concentration Risk [Line Items]
Concentration risk (as a percent)			41.00%	47.00%	42.00%	55.00%