Commitments and Contingencies - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) property	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) property	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Number of properties subject to ground leases | property	8		8
Operating lease right-of-use asset (Note 9)	$ 49,450		$ 49,450		$ 50,211
Operating lease liability (Note 9)	$ 23,649		$ 23,649		$ 23,985
Weighted average remaining lease term	32 years 6 months		32 years 6 months
Weighted average discount rate	4.33%		4.33%
Payments	$ 300		$ 700
Expense	$ 300	$ 300	$ 600	$ 700
Legal settlement reserve						$ 7,400
Asset management fees | Service Provider | Defendants vs. Service Providers
Loss Contingencies [Line Items]
Legal expenses				$ 1,000
Minimum
Loss Contingencies [Line Items]
Term of contract	16 years		16 years
Maximum
Loss Contingencies [Line Items]
Term of contract	85 years		85 years