Real Estate Properties - Narrative (Details) $ in Thousands, ft² in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) ft² property	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Real Estate [Abstract]
Real estate property improvements	$ 6,300	$ 11,600	$ 13,900
Committed expenditures on leases executed during period	$ 4,600
Square feet of leases committed for expenditures during the period (in sqft) | ft²	0.1
Committed but unspent tenant related obligations based on existing leases	$ 6,700
Number of real estate properties sold | property	0
COVID-19
Unusual or Infrequent Item, or Both [Line Items]
Deferred collection of rental income	$ 20	$ 300