Unrealized Gain / Loss on Investments (Details) (USD $)	3 Months Ended
	Mar. 31, 2013
CommonWealth REIT (CWH)
Unrealized gain on investments
Investment in common shares	250,000
Quoted market prices (in dollars per share)	$ 22.44
Weighted average costs (in dollars per share)	$ 26.00
Five Star
Unrealized gain on investments
Investment in common shares	4,235,000
Quoted market prices (in dollars per share)	$ 6.69
Weighted average costs (in dollars per share)	$ 3.36