Investment Activity - Schedule of Tenant Concentration of Revenue (Details) - Credit Concentration Risk - Sales Revenue, Net	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Texas Ten Tenant
Concentration Risk [Line Items]
Concentration risk percentage	23.20%	24.90%
Baylor Scott & White Health
Concentration Risk [Line Items]
Concentration risk percentage	21.40%	25.30%
Fundamental Healthcare
Concentration Risk [Line Items]
Concentration risk percentage	14.40%	15.20%
Life Generations Healthcare
Concentration Risk [Line Items]
Concentration risk percentage	12.60%	14.80%
Vibra Healthcare
Concentration Risk [Line Items]
Concentration risk percentage	11.40%	13.40%

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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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
-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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