Credit Concentration - Additional Information (Details)	9 Months Ended
Sep. 30, 2018 properties Rate
Concentration Risk [Line Items]
Number of properties, held for sale \| properties	2
Sales Revenue, Services, Net
Concentration Risk [Line Items]
Percent of ABR (annualized base rent) \| Rate	100.00%
Top five tenant relationships \| Sales Revenue, Services, Net \| Customer Concentration Risk
Concentration Risk [Line Items]
Percent of ABR (annualized base rent)	19.40%
CHI Portfolio \| Sales Revenue, Services, Net \| Customer Concentration Risk
Concentration Risk [Line Items]
Percent of ABR (annualized base rent)	19.50%

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
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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
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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