Operating Leases (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) property state	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) property state	Sep. 30, 2020 USD ($)
Operating Leases
Number of properties owned	7,018		7,018
Number of U.S. states where operating | state	50		50
Percentage rent received | $	$ 441	$ 532	$ 2,000	$ 2,300
Single-client properties
Operating Leases
Number of properties owned	6,961		6,961
Single-client properties as percentage of total properties	99.20%		99.20%
Properties available for lease or sale
Operating Leases
Number of properties owned	86		86