Real Estate Investments, Net (Geographic Concentrations) (Details) - property	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 31, 2020
Sales Revenue, Net | Geographic Concentration Risk | Florida (1)
Concentration Risk [Line Items]
Concentration risk, percentage	25.60%	23.10%
Sales Revenue, Net | Geographic Concentration Risk | Michigan (2)
Concentration Risk [Line Items]
Concentration risk, percentage	10.00%	10.90%
Assets Held-for-sale | Florida (1)
Concentration Risk [Line Items]
Number of properties held for sale	3
Seniors Housing Communities | Assets Held-for-sale
Concentration Risk [Line Items]
Number of properties held for sale			14
Seniors Housing Communities | Assets Held-for-sale | Florida (1)
Concentration Risk [Line Items]
Number of properties held for sale	2
Seniors Housing Communities | Assets Held-for-sale | Michigan (2)
Concentration Risk [Line Items]
Number of properties held for sale	11