Loans and Other Lending Investments, net (Details 6) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012 loans	Jun. 30, 2011 loans	Jun. 30, 2012 loans	Jun. 30, 2011 loans
Troubled debt restructurings
Number of loans restructured (in loans)	1		6
Trouble debt restructuring time period	1 year
Modifided loans	5		5
Senior mortgages
Troubled debt restructurings
Number of loans	1	1	6	4
Pre-modification recorded investment	$ 4,561,000	$ 20,380,000	$ 310,342,000	$ 126,051,000
Post-modification recorded investment	4,561,000	20,380,000	264,868,000	125,786,000
Senior mortgages troubled debt restructurings
Troubled debt restructurings
Number of loans	1	1	1	1
Outstanding recorded investment	26,120,000	28,328,000	26,120,000	28,328,000
Unfunded commitments	6,000,000		6,000,000
Performing senior mortgages
Troubled debt restructurings
Number of loans restructured (in loans)		1		4
Modifided loans	2		2
Recorded investment of loans whose maturity was extended	58,100,000		58,100,000
Additional number of loans restructured (in loans)		3
Weighted average maturity period of loans (in years)			0.4
Non-performing senior mortgages
Troubled debt restructurings
Number of loans restructured (in loans)			3
Non-performing senior mortgage with maturity of 0.7 years
Troubled debt restructurings
Modifided loans	1		1
Recorded investment of loans whose maturity was extended	48,200,000		48,200,000
Weighted average maturity period of loans (in years)			0.7
Financing receivable modifications weighted average maturity period of loans whose rate is reduced		1.4
Non-performing senior mortgage with maturity of 0.3 years
Troubled debt restructurings
Recorded investment of loans whose maturity was extended	18,000,000	105,700,000	18,000,000	105,700,000
Weighted average maturity period of loans (in years)			0.3
Weighted average maturity period of loans after reduction		4.70%	4.50%
Weighted average maturity rate of loans before reduction		8.30%	9.00%
Non-performing senior mortgage with outstanding principal balance reduced
Troubled debt restructurings
Pre-modification recorded investment	181,500,000		181,500,000
Financing receivable, charge-offs			$ 45,500,000
Variable rate basis of loans			LIBOR
Basis spread on variable rate of loans after reduction	3.50%		3.50%
Basis spread on variable rate of loans before reduction	7.00%		7.00%