Loans Receivable (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Number	Dec. 31, 2011 Number	Dec. 31, 2010 Number
Loans receivable by internal credit rating
Number of loans	12	12	2
Carrying Value of Loans Receivable	$ 211,250	$ 114,333	$ 110,395
Greater than zero [Member]
Loans receivable by internal credit rating
Number of loans	18	12
Carrying Value of Loans Receivable	211,250	114,333
Equal to zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable
Less than zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable
Whole Loan [Member]
Loans receivable by internal credit rating
Number of loans	8	3
Carrying Value of Loans Receivable	160,288	56,352
Whole Loan [Member] | Greater than zero [Member]
Loans receivable by internal credit rating
Number of loans	8	3
Carrying Value of Loans Receivable	160,288	56,352
Whole Loan [Member] | Equal to zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable
Whole Loan [Member] | Less than zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable
B Note [Member]
Loans receivable by internal credit rating
Number of loans	5	2
Carrying Value of Loans Receivable	31,028	21,534
B Note [Member] | Greater than zero [Member]
Loans receivable by internal credit rating
Number of loans	5	2
Carrying Value of Loans Receivable	31,028	21,534
B Note [Member] | Equal to zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable
B Note [Member] | Less than zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable
Mezzanine [Member]
Loans receivable by internal credit rating
Number of loans	5	7
Carrying Value of Loans Receivable	19,934	36,447
Mezzanine [Member] | Greater than zero [Member]
Loans receivable by internal credit rating
Number of loans	5	7
Carrying Value of Loans Receivable	19,934	36,447
Mezzanine [Member] | Equal to zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable
Mezzanine [Member] | Less than zero [Member]
Loans receivable by internal credit rating
Number of loans
Carrying Value of Loans Receivable