Fair Value Measurements Assets and Liabilities Measured on a Non-Recurring Basis (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Valuation adjustments to investments in unconsolidated joint ventures	$ 0	$ 390	$ 1,029
Fair Value, Significant Unobservable Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long Lived Real Estate Assets Fair Value Disclosure	5,494	6,658	44,629
Real Estate Related Impairments	5,805	3,502	21,993
Long Lived Assets Initial Basis	11,299	10,160	66,622
Total Fair Value Measurements - Non-Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in unconsolidated joint ventures		$ 1,050	$ 970