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Basis of Presentation - Narratives (Details) $ in Thousands	3 Months Ended		9 Months Ended
Basis of Presentation - Narratives (Details) $ in Thousands	Sep. 30, 2021 USD ($) variable_interest_entity vie	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) variable_interest_entity vie	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) variable_interest_entity
Basis of Consolidation
Variable interest entities, count \| variable_interest_entity	12		12		12
Variable interest entities consolidated, count	4		4		5
Variable interest entities unconsolidated, count \| variable_interest_entity	8		8		7
Equity method investments in real estate	$ 361,835		$ 361,835		$ 283,446
Real Estate
Basis of Consolidation
Gross contract revenue	4,050	$ 1,974	9,474	$ 9,368
Real Estate \| Hotel
Basis of Consolidation
Gross contract revenue	2,400	$ 600	4,900	$ 5,300
Variable Interest Entity
Basis of Consolidation
Equity method investments in real estate	$ 584,800		$ 584,800		$ 425,300
Managed Programs
Basis of Consolidation
Variable interest entities unconsolidated, count \| variable_interest_entity	2		2		2
Real Estate
Basis of Consolidation
Variable interest entities unconsolidated, count \| variable_interest_entity	6		6		5
Equity method investments in real estate	$ 296,394		$ 296,394		$ 226,889