Real Estate Investments - Property Sales (Details)	3 Months Ended				6 Months Ended
	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($) property item	Jun. 30, 2019 USD ($)	Jun. 30, 2018 property	Jun. 30, 2020 USD ($) item property	Mar. 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Disposals and other
Carrying value	$ 1,115,593,000				$ 1,115,593,000			$ 1,136,816,000
Net Gain	189,000		$ 500,000		$ 44,043,000		$ 500,000
ALF
Disposals and other
Number of properties sold | property				6
Properties sold
Disposals and other
Number of properties sold | property					21
Number of beds or units in property sold | item					2,411
Sales price					$ 74,800,000
Carrying value	29,084,000				29,084,000
Net Gain					44,043,000		$ 500,000
Net Gain					102,000
Holdback repayment					90,000
Reassessment adjustment					$ 12,000
Properties sold | SNF | Arizona
Disposals and other
Number of properties sold | property					1
Number of beds or units in property sold | item					194
Sales price					$ 12,550,000
Carrying value	2,229,000				2,229,000
Net Gain					$ 10,292,000
Properties sold | SNF | Colorado
Disposals and other
Number of properties sold | property					3
Number of beds or units in property sold | item					275
Sales price					$ 15,000,000
Carrying value	4,271,000				4,271,000
Net Gain					$ 10,364,000
Properties sold | SNF | Kansas
Disposals and other
Number of properties sold | property					3
Number of beds or units in property sold | item					250
Sales price					$ 9,750,000
Carrying value	7,438,000				7,438,000
Net Gain					$ 1,993,000
Properties sold | SNF | Iowa
Disposals and other
Number of properties sold | property					7
Number of beds or units in property sold | item					544
Sales price					$ 14,500,000
Carrying value	4,886,000				4,886,000
Net Gain					9,005,000
Holdback amount	150,000	$ 838,000			150,000	$ 838,000
Realizable holdback amount		$ 471,000			$ 91,000
Properties sold | SNF | Texas
Disposals and other
Number of properties sold | property					7
Number of beds or units in property sold | item					1,148
Sales price					$ 23,000,000
Carrying value	$ 10,260,000				10,260,000
Net Gain					$ 12,287,000
Preferred Care, Inc.
Disposals and other
Number of properties sold | property		21
Number of beds or units in property sold | item		2,411
Net Gain		$ 44,043,000				$ 44,000,000