Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
State	$ 424	$ 574	$ 576
Total	424	574	576
Income tax provision	$ 424	$ 574	$ 576
Reconciliation of effective tax rate and the U.S. federal statutory income tax rate
Taxes at statutory U.S. federal income tax rate	35.00%	35.00%	35.00%
Nontaxable income of SNH	(35.00%)	(35.00%)	(35.00%)
State and local income taxes, net of federal tax benefit	0.30%	0.40%	0.30%
Change in valuation allowance	3.58%	8.82%	6.39%
Other differences, net	(3.58%)	(8.82%)	(6.39%)
Effective tax rate	0.30%	0.40%	0.30%
Deferred tax assets:
Deferred income	$ 2,512	$ 2,862
Other	222	115
Tax loss carryforwards	33,626	27,941
Deferred tax assets, gross	36,360	30,918
Valuation allowance	$ (36,360)	$ (30,918)
Percentage of valuation allowance provided	100.00%	100.00%
Tax Credit Carryforward, Amount	$ 84,688