Real Estate Investments - Operator changes (Details)					1 Months Ended		3 Months Ended		9 Months Ended	12 Months Ended
	Jun. 01, 2020 USD ($)	Oct. 04, 2019 USD ($)	Jun. 01, 2019 USD ($)	Dec. 04, 2018	Oct. 31, 2019 USD ($)	Jul. 31, 2019 USD ($) item	Sep. 30, 2019 USD ($) item	Jun. 30, 2019 USD ($) item	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2017 property lease
Other disclosures
Rental income							$ 38,665,000		$ 114,566,000
Contractual rent (as a percent)							50.00%
Rent in year two							$ 132,387,000		132,387,000
Rent in year three							124,338,000		124,338,000
Rent in year four							125,420,000		$ 125,420,000
Georgia and South Carolina
Other disclosures
Rent on cash basis							$ 1,762,000
Florida
Other disclosures
Increase in Lease Rent (as a percent)							3.50%
Anthem Memory Care
Other disclosures
Number of properties in default | property											11
Anthem Memory Care | Forecast
Other disclosures
Minimum cash rent received										$ 7,500,000
Percentage of contractual amount due										50.00%
Preferred Care, Inc.
Other disclosures
Minimum cash rent received							$ 55,000
Number of properties under two master leases | property											24
Number of master leases | lease											2
Minimum cash rent receivable							$ 1,000,000
Preferred Care, Inc. | Subsequent Event
Other disclosures
Rental income					$ 55,000
Thrive
Other disclosures
Initial lease term							2 years	10 years	2 years
Rent in year one								$ 1,250,000
Rent in year two								1,500,000
Rent in year three								1,975,000
Rent in year four								$ 2,150,000
Rent on cash basis									$ 700,000
Master lease in default
Other disclosures
Increase in Lease Rent			$ 400,000
Master lease in default | Forecast
Other disclosures
Increase in Lease Rent	$ 300,000
Increase in Lease Rent (as a percent)	2.50%
ALF and MC | Thrive
Other disclosures
Number of properties in transition | item							2
120 units | MC | Thrive | Ohio and Kentucky
Other disclosures
Number of properties in transition | item								2
Number of units in transition | item								120
56-unit MC | Texas
Other disclosures
Number of properties in transition | item								56
159 units | Georgia and South Carolina
Other disclosures
Number of properties in transition | item							159
60-unit MC | Florida
Other disclosures
Initial lease term						10 years
Number of properties in transition | item						60
Rent in year two						$ 450,000
Rent in year three						600,000
60-unit MC | Maximum | Florida
Other disclosures
Deferred lease payments						$ 150,000
Senior Care Centers
Other disclosures
Petition Date and Reject The Lease Period				120 days
Petition Date and Reject The Lease Additional Period				90 days
Court ordered payment amount		$ 1,596,000