Noncash Investing and Financing Activities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Other Significant Noncash Transactions [Line Items]
Accrued dividends and distributions payable	$ 54,394	$ 54,569
Additions to real estate assets accrued but not yet paid	14,513	5,326
Decrease in noncontrolling interest and joint venture interest	2,231
Corporate Joint Venture
Other Significant Noncash Transactions [Line Items]
Decrease in real estate assets	(9,131)	0
Decrease in mortgage and other indebtedness	2,466	0
Decrease in operating assets and liabilities	1,287	0
Decrease in noncontrolling interest and joint venture interest	2,231	0
Partnership Interest
Other Significant Noncash Transactions [Line Items]
Decrease in real estate assets	0	(14,025)
Decrease in operating assets and liabilities	0	(5)
Increase in investment in unconsolidated affiliate	0	14,030
Outlet Shoppes at Atlanta - Ridgewalk
Other Significant Noncash Transactions [Line Items]
Decrease in real estate assets	(28,218)	0
Decrease in mortgage and other indebtedness	31,953	0
Decrease in operating assets and liabilities	$ 320	$ 0