Notes and Other Receivables (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013 Notes		Jun. 30, 2013 Notes		Mar. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 110,544,000		$ 110,544,000			$ 66,163,000
Income related acceleration			800,000
Variable rate basis	LIBOR + 1.75%		LIBOR + 2.5%
Basis spread on rate (in hundredths)	2.50%		2.50%
Number of notes for which payment was received	3		3
Proceeds from notes receivable	26,000,000		30,500,000
Short term Bridge Loan	42,400,000		42,400,000		26,000,000
Secured Due December 2014 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	3,212,000	[1]	3,212,000	[1]		3,212,000	[1]
Stated interest rate (in hundredths)			4.00%
Secured Due May 2013 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	0		0			971,000
Stated interest rate (in hundredths)			8.00%
Secured Due March 2013 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	0		0			10,800,000
Stated interest rate (in hundredths)			8.80%
Secured Effective March 2013 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	0		0			18,499,000
Stated interest rate (in hundredths)			9.60%
Wesco III [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Stated interest rate (in hundredths)	3.10%
Variable rate basis	LIBOR + 2.50%
Basis spread on rate (in hundredths)	2.50%		2.50%
Proceeds from notes receivable	27,300,000
Short term Bridge Loan	56,800,000		56,800,000
Term of loan	7 years
Note and Other Receivables From Affiliates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	103,869,000	[2]	103,869,000	[2]		28,896,000	[2]
Other Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 3,463,000		$ 3,463,000			$ 3,785,000

[1] The borrower funds an impound account for capital replacement.

[2] During the second quarter of 2013, the Company provided short-term bridge loans to Fund II and Wesco III of $42.4 million and $56.8 million, respectively, at rates of LIBOR + 1.75% and LIBOR + 2.50%, respectively.