Fair Value Measurements (Details 1) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016		Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total impairment losses, investment properties	$ 8,390	[1]	$ 0
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total impairment losses, investment properties	8,390		0
Total Asset Impairment Charges	8,390		0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	39,150		0
Assets, Fair Value Disclosure	$ 39,150		$ 0

[1] Total provision for asset impairment included $8,390 related to two retail assets.