Notes Receivable (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Loans receivable on real estate
Balance at beginning of period	$ 103,705	$ 58,719	$ 115,419
Additions:
New mortgage loans	10,000	60,618	6,197
Interest	811	3,106	9,355
Accretion of discount	780	250	0
Deductions:
Collections of principal	(25,755)	0	0
Loan foreclosure	0	(18,988)	0
Loan loss reserve	(5,000)	0	(72,252)
Balance at close of period	$ 84,541	$ 103,705	$ 58,719