Supplemental Disclosure of Statement of Cash Flow Information Other Noncash Transactions (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 properties	Dec. 31, 2011 properties	Dec. 31, 2010 properties
Other Significant Noncash Transactions [Line Items]
Interest paid	$ 101,262	$ 103,427	$ 114,031
Income taxes paid	1,018	1,289	1,019
Debt satisfaction gains (charges), net	(8,062)	(311)	3,590
Real estate number of properties sold (in # of properties)	14	17	13
Interests Sold [Member]
Other Significant Noncash Transactions [Line Items]
Real estate non-recourse mortgage debt assumed	28,648		74,504
Real estate number of properties sold (in # of properties)	3		3
Seller financing	3,003
Conveyed Interest [Member]
Other Significant Noncash Transactions [Line Items]
Properties with conveyed interest	2
Debt conversion, original debt, amount	12,409
Debt satisfaction gains (charges), net	317
Property Owner Subsidiary [Member]
Other Significant Noncash Transactions [Line Items]
Real estate non-recourse mortgage debt assumed	$ 8,921