Investments in Real Estate Entities (Details 4) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary of the Company's equity in income of unconsolidated entities
Gain on sale of communities	$ 21,748	$ 54,202	$ 136,333
Fund II
Summary of the Company's equity in income of unconsolidated entities
Equity in income of unconsolidated entities relating to the Company's recognition of promoted interest		925	26,472
Gain on sale of communities			$ 26,322
Avalon Kirkland at Carillon [Member] | US Fund
Summary of the Company's equity in income of unconsolidated entities
Gain on sale of communities		$ 8,636