Concentration of Credit Risk - Schedule of Concentration of Credit Risk (Details) - property	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Senior housing triple-net
Concentration Risk [Line Items]
Number of properties classified as held for sale	64
Brookdale Senior Living | Total Assets | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk (as a percent)	10.00%	17.00%
Brookdale Senior Living | Revenue | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk (as a percent)	8.00%	12.00%	13.00%
Brookdale Senior Living | Senior housing triple-net | Total Assets | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk (as a percent)	39.00%	69.00%
Brookdale Senior Living | Senior housing triple-net | Revenue | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk (as a percent)	47.00%	59.00%	58.00%