Schedule II - Valuation and Qualifying Accounts (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation and Qualifying Accounts Disclosure [Line Items]
Real Estate, Federal Income Tax Basis	$ 4,000,000,000
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance at Beginning of Period	16,646,000	15,485,000	15,222,000
Valuation Allowances and Reserves, Additions	1,384,000	1,891,000	928,000
Valuation Allowances and Reserves, Deductions	1,782,000	730,000	665,000
Valuation Allowances and Reserves, Balance at End of Period	$ 16,248,000	$ 16,646,000	$ 15,485,000