Revenues (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Revenues [Abstract]
Unpaid billed charges of rent and tenant reimbursements	$ 0.3	$ 1.3
Unrecorded revenue from tenants	$ 0.3	$ 1.3