Real Estate Investments - Development and Improvement Projects (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Real estate investments
Invested in projects	$ 22,992
Development | Development and Improvement Commitments
Real estate investments
Invested in projects	13,939	$ 35,623
Improvements | Development and Improvement Commitments
Real estate investments
Invested in projects	2,308	5,566
ALF | Development | Development and Improvement Commitments
Real estate investments
Invested in projects	10,366	35,623
ALF | Improvements | Development and Improvement Commitments
Real estate investments
Invested in projects	951	2,134
SNF | Development | Development and Improvement Commitments
Real estate investments
Invested in projects	3,573
SNF | Improvements | Development and Improvement Commitments
Real estate investments
Invested in projects	$ 1,357	$ 3,432