SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance at beginning of year	$ 0	$ 1,500,000	$ 10,335,000
Additions: [Abstract]
New mortgage loan	3,523,000	0	0
Amortization of mortgage loan discount	0	0	400,000
Deductions: [Abstract]
Mortgage Loans on Real Estate, Other Deductions	(21,000)	(1,500,000)	0
Non-cash impairment loss on mortgage loan receivable	0	0	(9,235,000)
Balance at end of year	3,502,000	0	1,500,000
US Airways Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate (in percent)	3.00%
Final Maturity Date	Dec. 01, 2016
Periodic Payment Term	Interest only
Prior Liens	0
Face Amount of Mortgage	3,545,000
Cost for federal tax purposes	3,502,000
Principal Amount of Loan Subject to Delinquent Principal and Interest	$ 0