Investments in Real Estate - Investments in Existing Properties Narrative (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Investments in real estate properties
Capitalized costs on existing portfolio	$ 11,159	$ 10,336
Investments in existing properties
Investments in real estate properties
Capitalized costs on existing portfolio	11,100	5,100
Re-leasing costs	2,000	1,000
Recurring capital expenditures	416	126
Non-recurring building improvements	$ 8,700	$ 4,000