Investments in Unconsolidated Real Estate Joint Ventures Management, Leasing and Marketing Fees (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Management, Leasing and Marketing Fees [Line Items]
Management and Leasing Fees Paid by Unconsolidated Joint Ventures	$ 479	$ 505
Marketing Fees Paid by Unconsolidated Joint Venture	53	44
Total Management, Leasing and Marketing Fees Paid by Unconsolidated Joint Ventures	$ 532	$ 549