Real Estate Investments - Mortgage Loan Activity (Details) - Mortgage Loans $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) loan state item property $ / item	Sep. 30, 2016 USD ($)
Mortgage Loans
Originations and fundings under mortgage loans receivable	$ 9,333	$ 19,113
Pay-offs received	(16,665)	(746)
Scheduled principal payments received	(686)	(1,371)
Net (decrease) increase in mortgage loans receivable	$ (8,018)	$ 16,996
Minimum
Mortgage Loans
Interest rate for mortgage loan (as a percent)	9.40%
General amortization schedule of mortgage loans	20 years
Specified basis points for annual increase in interest rate (as a percent)	0.10%
Maximum
Mortgage Loans
Interest rate for mortgage loan (as a percent)	11.20%
General amortization schedule of mortgage loans	30 years
Specified basis points for annual increase in interest rate (as a percent)	0.25%
SNF
Mortgage Loans
Gross Investments	$ 224,095
Number of Loans | loan	5
Number of properties | property	21
Investment per Bed/Unit | $ / item	81.08
Number of states | state	2
Number of operators | state	2
SNF Beds | SNF
Mortgage Loans
Number of beds/units | item	2,764