Loans Receivable (Details 3) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013 Number	Dec. 31, 2012 Number
Loans receivable by internal credit rating
Number of loans	15	18
Carrying Value of Loans Receivable	$ 130,212,000	$ 211,250,000
Greater than zero [Member]
Loans receivable by internal credit rating
Number of loans	14	18
Carrying Value of Loans Receivable	119,889,000	211,250,000
Equal to zero [Member]
Loans receivable by internal credit rating
Number of loans	1
Carrying Value of Loans Receivable	10,323,000
Less than zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable