Real Estate (Schedule of Pro Forma Information on Legend Business Acquisition) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended			2 Months Ended	12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 Acquisition Legend Healthcare [Member]	Dec. 31, 2011 Acquisition Legend Healthcare [Member]	Dec. 31, 2010 Acquisition Legend Healthcare [Member]
Rental income									$ 76,050	$ 71,289	$ 53,648	$ 644
Net Income	18,114	18,808	25,117	19,093	16,954	17,334	19,189	15,944	81,132	69,421	64,229	440
Business Acquisition, Pro Forma Revenue													86,764	81,912
Business Acquisition, Pro Forma Net Income (Loss)													$ 83,969	$ 72,076