Real Estate - Lease Concessions Related to COVID-19 (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020
COVID-19 Pandemic
Unusual or Infrequent Item, or Both [Line Items]
Deferred rent receivables	$ 0.4
Forgiveness of rent	$ 0.6
Forecast | COVID-19 Pandemic
Unusual or Infrequent Item, or Both [Line Items]
Forgiveness of rent		$ 0.6
Minimum
Unusual or Infrequent Item, or Both [Line Items]
Term for deferred rent	2 months
Term for repayment of deferred rent	3 months
Maximum
Unusual or Infrequent Item, or Both [Line Items]
Term for deferred rent	3 months
Term for repayment of deferred rent	17 months