Real Estate - Schedule of Development in Process Activities (Parenthetical) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Notes receivable, net	$ 101,450	$ 114,943	$ 111,775	$ 160,991
Impairment charge	72,842
Fund II
Property, Plant and Equipment [Line Items]
Notes receivable, net	33,800
Fund Portfolio | Fund IV
Property, Plant and Equipment [Line Items]
Impairment charge	$ 16,500