Investments in Unconsolidated Real Estate Joint Ventures Management, Leasing and Marketing Fees (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Management, Leasing and Marketing Fees [Line Items]
Management and Leasing Fees Paid by Unconsolidated Joint Ventures	$ 474	$ 469	$ 953	$ 973
Marketing Fees Paid by Unconsolidated Joint Venture	47	44	100	88
Total Management, Leasing and Marketing Fees Paid by Unconsolidated Joint Ventures	$ 521	$ 513	$ 1,053	$ 1,061