Property Portfolio - (Details)

v3.20.2

Property Portfolio - (Details) $ in Thousands																									1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) lease	Sep. 18, 2020 USD ($)	Jul. 31, 2020 USD ($) tenant lease	Jul. 17, 2020 USD ($)	Jul. 16, 2020 USD ($)	Apr. 27, 2020 USD ($)	Mar. 20, 2020 USD ($) lease	Mar. 04, 2020 USD ($)	Feb. 27, 2020 USD ($)	Feb. 13, 2020 USD ($)	Dec. 17, 2019 USD ($)	Nov. 15, 2019 USD ($)	Oct. 31, 2019 USD ($)	Oct. 25, 2019 USD ($)	Oct. 01, 2019 USD ($)	Sep. 26, 2019 USD ($)	Aug. 23, 2019 USD ($) property	Aug. 14, 2019 USD ($) lease	Aug. 06, 2019 USD ($)	Aug. 05, 2019 USD ($) lease	Aug. 01, 2019 USD ($) lease	Jul. 12, 2019 USD ($)	Apr. 15, 2019 USD ($) lease	Feb. 28, 2019 USD ($)	Mar. 19, 2019 USD ($) lease property	Sep. 30, 2020 USD ($) lease	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) lease property	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) property
Property, Plant and Equipment [Line Items]
Number of Properties Acquired | property																												10		18
Depreciation, Total																										$ 6,954	$ 5,006	$ 19,383	$ 13,481
Tenant Improvement Allowances Receivable	$ 20,164																									20,164		20,164
Capital Lease Obligations, Noncurrent	$ 9,233																									$ 9,233		9,233
Property, Plant and Equipment, Additions																												$ 155,851		$ 257,979
Debt Instrument, Term																												3 years 21 days		3 years 9 months 3 days
Operating Lease, Weighted Average Remaining Lease Term	41 years																									41 years		41 years
Commercial mortgage-backed securities (CMBS)
Property, Plant and Equipment [Line Items]
Debt Instrument, Face Amount						$ 12,100
Debt Instrument, Interest Rate, Stated Percentage						4.68%
Debt Instrument, Term						4 years
Revolving Credit Facility [Member]
Property, Plant and Equipment [Line Items]
Debt Instrument, Face Amount	$ 600,000																									$ 600,000		$ 600,000
Lease Intangibles Asset [Member]
Property, Plant and Equipment [Line Items]
Finite-Lived Intangible Asset, Useful Life																												5 years 6 months
Lease Intangibles Liability [Member]
Property, Plant and Equipment [Line Items]
Finite-Lived Intangible Asset, Useful Life																												5 years 1 month 6 days
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												$ 20,742		$ 31,671
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
Number or leases assumed | lease																									2
Number of new leases entered into | lease																									3
Gilbert Arizona Medical Office Buildings [Member]
Property, Plant and Equipment [Line Items]
Number of medical offices | property																									2
Chandler Arizona Medical Office Suites [Member]
Property, Plant and Equipment [Line Items]
Number of medical offices | property																									2
Dobson Facility [Member]
Property, Plant and Equipment [Line Items]
Lessor, Operating Lease, Term of Contract																									10 years 6 months
IRF Portfolio [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																							$ 94,600
Number or leases assumed | lease																							4
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
San Marcos [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														2,322
Lansing [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																					$ 11,100									11,368
Number or leases assumed | lease																					4
Number of new leases entered into | lease																					2
Operating Lease, Weighted Average Remaining Lease Term																					8 years 6 months
Lansing [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														1,202
Bannockburn [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																				$ 6,800										6,977
Number or leases assumed | lease																				14
Operating Lease, Weighted Average Remaining Lease Term																				6 years 3 months 18 days
Bannockburn [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														763
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
Aurora [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														1,521
Livonia [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																		$ 10,400												10,592
Number or leases assumed | lease																		10
Operating Lease, Weighted Average Remaining Lease Term																		3 years 2 months 12 days
Livonia [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														980
Gilbert [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																	$ 5,600													5,592
Number of medical offices | property																	2
Operating Lease, Weighted Average Remaining Lease Term																	10 years
Gilbert [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														2,408
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
Morgantown [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														883
Beaumont [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions															$ 33,700															33,739
Finite-Lived Intangible Asset, Useful Life															10 years
Beaumont [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														3,022
Bastrop [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions														$ 12,100																12,065
Finite-Lived Intangible Asset, Useful Life														5 years
Bastrop [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														1,975
Panama City [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions													$ 13,000																	12,976
Finite-Lived Intangible Asset, Useful Life													15 years
Panama City [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														1,559
Jacksonville [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions												$ 8,900																		8,869
Finite-Lived Intangible Asset, Useful Life												15 years
Jacksonville [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														1,023
Greenwood [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions											$ 5,800																			5,848
Finite-Lived Intangible Asset, Useful Life											13 years
Greenwood [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																														$ 892
LTAC Hospital [Member]
Property, Plant and Equipment [Line Items]
Lessor, Operating Lease, Term of Contract																								16 years
High Point Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions										$ 25,100																		25,081
Lessor, Operating Lease, Term of Contract										3 years
High Point Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												1,749
Clinton Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions									$ 11,600																			11,619
Lessor, Operating Lease, Term of Contract									4 years
Clinton Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												664
West Allis Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions								$ 9,100																				9,357
Lessor, Operating Lease, Term of Contract								4 years
West Allis Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												974
Grand Rapids Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions							$ 22,700																					22,790
Number or leases assumed | lease							11
Lessor, Operating Lease, Term of Contract							5 years
Grand Rapids Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												2,947
Dumfries Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions						$ 19,600
Lessor, Operating Lease, Term of Contract						9 years 6 months
Centerville Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions					$ 5,100																							5,071
Lessor, Operating Lease, Term of Contract					10 years 6 months
Centerville Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Operating Lease, Weighted Average Remaining Lease Term					49 years
Fairfax Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions				$ 17,900																								19,745
Lessor, Operating Lease, Term of Contract				9 years 1 month 6 days
Fairfax Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												6,731
Rosedale Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions			$ 23,100																									23,891
Debt Instrument, Face Amount			$ 14,800
Debt Instrument, Interest Rate, Stated Percentage			3.85%
Debt Instrument, Term			5 years
Number or leases assumed | lease			8
Number of tenants assumed | tenant			6
Lessor, Operating Lease, Term of Contract			6 years 7 months 6 days
Rosedale Facilities [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												2,856
Lancaster Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions		$ 6,300																										6,305
Lessor, Operating Lease, Term of Contract		8 years 6 months
Lancaster Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												696
Winston-Salem Facility [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions	$ 8,500																											$ 9,240
Number or leases assumed | lease	5																									5		5
Lessor, Operating Lease, Term of Contract	4 years																									4 years		4 years
Winston-Salem Facility [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Additions																												$ 1,524