| Property Portfolio - Additional Information (Details)$ in Thousands
 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  | 
| Sep. 26, 2019  USD ($) | Aug. 23, 2019  USD ($) | Aug. 14, 2019  USD ($) | Aug. 06, 2019  USD ($) | Aug. 05, 2019  USD ($) | Aug. 01, 2019  USD ($) | Jul. 12, 2019  USD ($) | Apr. 15, 2019  USD ($) | Aug. 03, 2018  USD ($) | Jul. 03, 2018  USD ($) | Apr. 19, 2018  USD ($) | Mar. 22, 2018  USD ($) | Mar. 01, 2018  USD ($) | Feb. 23, 2018  USD ($) | Feb. 09, 2018  USD ($) | Jan. 24, 2018  USD ($) | Mar. 19, 2019  USD ($) | Feb. 28, 2018  USD ($) | Sep. 30, 2019  USD ($) | Sep. 30, 2018  USD ($) | Sep. 30, 2019  USD ($)  property | Sep. 30, 2018  USD ($) | Feb. 28, 2019 | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Number of Properties Acquired | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13 |  |  | 
| Depreciation, Total |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,006 | $ 3,614 | $ 13,481 | $ 9,965 |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 182,896 | 141,530 |  | 
| Tenant Improvement Allowances Receivable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 19,137 |  | $ 19,137 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24 years |  | 24 years |  |  | 
| Capital Lease Obligations, Noncurrent |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10,867 |  | $ 10,867 |  |  | 
| Lease Intangibles Asset [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Finite-Lived Intangible Asset, Useful Life |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 years 5 months 1 day |  |  | 
| Lease Intangibles Liability [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Finite-Lived Intangible Asset, Useful Life |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 years 4 months 28 days |  |  | 
| Zachary Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,600 |  |  |  |  |  | 
| Lessor, Operating Lease, Term of Contract |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 46 years | 
| Gilbert And Chandler Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 16,300 |  |  |  |  |  |  | 
| Dobson Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Lessor, Operating Lease, Term of Contract |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years 6 months |  |  |  |  |  |  | 
| Moline Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  | 
| Fresenius Medical Care Quad Cities [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13 years |  |  |  |  |  |  |  | 
| Quad Cities Nephrology Associates [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15 years |  |  |  |  |  |  |  | 
| Silvis facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 67 years |  |  |  |  |  |  |  | 
| Fresenius [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13 years |  |  |  |  |  |  |  | 
| Moline Silvis Facilities[Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,900 |  |  |  |  |  |  |  | 
| Freemont [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 8,500 |  |  |  |  |  |  | 8,497 |  | 
| Lessor, Operating Lease, Term of Contract |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 years |  |  |  |  |  |  |  |  | 
| Gainesville [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10,500 |  |  |  |  |  |  |  | 10,510 |  | 
| Lessor, Operating Lease, Term of Contract |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 years |  |  |  |  |  |  |  |  |  | 
| Dallas [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  |  | $ 23,300 |  |  |  |  |  |  |  |  | 23,284 |  | 
| Orlando Facilities [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  |  | $ 16,400 |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  |  | 4 years 6 months |  |  |  |  |  |  |  |  |  |  |  | 
| Belpre Portfolio [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  |  | $ 64,100 |  |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  |  |  | 11 years 4 months 6 days |  |  |  |  |  |  |  |  |  |  |  |  | 
| McAllen [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  |  | $ 5,400 |  |  |  |  |  |  |  |  |  |  |  | 5,395 |  | 
| Lessor, Operating Lease, Term of Contract |  |  |  |  |  |  |  |  |  | 11 years |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| IRF Portfolio [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  | $ 94,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  | 8 years 3 months 18 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| San Marcos [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  | $ 12,000 |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 11,974 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  | 8 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Lansing [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  | $ 11,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11,368 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  | 8 years 6 months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Bannockburn [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  | $ 6,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,689 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  | 6 years 3 months 18 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Aurora [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  | $ 12,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12,557 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  | 6 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Livonia [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  | $ 10,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,592 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  | 3 years 2 months 12 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Gilbert [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  | $ 5,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,592 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Morgantown [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions | $ 8,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,950 |  |  | 
| Operating Lease, Weighted Average Remaining Lease Term | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Derby [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment, Additions |  |  |  |  |  |  |  |  | $ 3,600 |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,604 |  | 
| Operating Lease, Weighted Average Remaining Lease Term |  |  |  |  |  |  |  |  | 9 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| LTAC Hospital [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
| Lessor, Operating Lease, Term of Contract |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 16 years |