Reportable Segments (Net Income (Loss) Reconciliation) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation from Segment Totals to Consolidated
Gain on sale of third party management and leasing business	$ (4,577,000)	$ (7,459,000)	$ 0
Interest expense	(520,000)	(1,985,000)	(197,000)
Reimbursed Expenses	(5,215,000)	(7,063,000)	(6,208,000)
Gains (Losses) on Extinguishment of Debt	0	(94,000)	0
Dividends, Preferred Stock	(10,008,000)	(12,907,000)	(12,907,000)
Other adjustments		(1,824,000)
NET INCOME (LOSS) AVAILABLE TO COMMON STOCKHOLDERS	109,097,000	32,821,000	(141,332,000)
Total Assets	2,273,206,000	1,124,242,000
Office
Reconciliation from Segment Totals to Consolidated
Net operating income	122,503,000	80,907,000	75,387,000
Fee income	0	0	0
Sales less costs of sales	0	0	0
Other income	0	0	0
Gain on sale of third party management and leasing business	0	0
Third party management and leasing expenses	0	0	0
Interest expense	0	0	0
Separation expenses	0	0	0
Reimbursed Expenses	0	0	0
General and administrative expenses	0	0	0
Other expenses		0	0
Gains (Losses) on Extinguishment of Debt		0	0
Impairment loss	0	0	0
Dividends, Preferred Stock	0	0	0
Funds from operations available to common stockholders	122,503,000	80,907,000	75,387,000
Total Assets	2,163,123,000	736,867,000	732,857,000
Retail
Reconciliation from Segment Totals to Consolidated
Net operating income	13,278,000	29,429,000	31,583,000
Fee income	0	0	0
Sales less costs of sales	0	0	0
Other income	0	0	0
Gain on sale of third party management and leasing business	0	0
Third party management and leasing expenses	0	0	0
Interest expense	0	0	0
Separation expenses	0	0	0
Reimbursed Expenses	0	0	0
General and administrative expenses	0	0	0
Other expenses		0	0
Gains (Losses) on Extinguishment of Debt		0	0
Impairment loss	0	0	0
Dividends, Preferred Stock	0	0	0
Funds from operations available to common stockholders	13,278,000	29,429,000	31,583,000
Total Assets	18,112,000	151,417,000	375,923,000
Land
Reconciliation from Segment Totals to Consolidated
Net operating income	0	0	0
Fee income	1,273,000	4,915,000	5,236,000
Sales less costs of sales	0	0	0
Other income	0	0	0
Gain on sale of third party management and leasing business	0	0
Third party management and leasing expenses	0	0	0
Interest expense	0	0	0
Separation expenses	0	0	0
Reimbursed Expenses	0	0	0
General and administrative expenses	0	0	0
Other expenses		0	0
Gains (Losses) on Extinguishment of Debt		0	0
Impairment loss	0	0	0
Dividends, Preferred Stock	0	0	0
Funds from operations available to common stockholders	1,273,000	4,915,000	5,236,000
Total Assets	47,235,000	50,520,000	108,172,000
Third Party Management and Leasing
Reconciliation from Segment Totals to Consolidated
Net operating income	0	0	0
Fee income	0	0	0
Sales less costs of sales	76,000	16,365,000	19,359,000
Other income	0	0	0
Gain on sale of third party management and leasing business	4,576,000	7,459,000
Third party management and leasing expenses	(97,000)	(13,675,000)	(16,585,000)
Interest expense	0	0	0
Separation expenses	0	0	0
Reimbursed Expenses	0	0	0
General and administrative expenses	0	0	0
Other expenses		0	0
Gains (Losses) on Extinguishment of Debt		0	0
Impairment loss	0	0	0
Dividends, Preferred Stock	0	0	0
Funds from operations available to common stockholders	4,555,000	10,149,000	2,774,000
Total Assets	0	0	4,302,000
Other
Reconciliation from Segment Totals to Consolidated
Net operating income	2,299,000	121,000	3,583,000
Fee income	191,000	309,000	2,250,000
Sales less costs of sales	10,891,000	17,797,000	13,821,000
Other income	3,528,000	5,153,000	2,204,000
Gain on sale of third party management and leasing business	0	0
Third party management and leasing expenses	0	0	0
Interest expense	(520,000)	(1,985,000)	(197,000)
Separation expenses	(21,940,000)	(23,208,000)	(24,166,000)
Reimbursed Expenses	(5,215,000)	(7,063,000)	(6,208,000)
General and administrative expenses	(29,672,000)	(28,154,000)	(32,515,000)
Other expenses		(488,000)	(129,134,000)
Gains (Losses) on Extinguishment of Debt		(94,000)	(74,000)
Impairment loss	(11,373,000)	(8,389,000)	(8,512,000)
Dividends, Preferred Stock	(12,664,000)	(12,907,000)	(12,907,000)
Funds from operations available to common stockholders	(64,475,000)	(58,908,000)	(191,855,000)
Total Assets	44,736,000	185,438,000	14,281,000
Total
Reconciliation from Segment Totals to Consolidated
Net operating income	138,080,000	110,457,000	110,553,000
Fee income	1,464,000	5,224,000	7,486,000
Sales less costs of sales	10,967,000	34,162,000	33,180,000
Other income	3,528,000	5,153,000	2,204,000
Gain on sale of third party management and leasing business	4,576,000	7,459,000
Third party management and leasing expenses	(97,000)	(13,675,000)	(16,585,000)
Interest expense	(520,000)	(1,985,000)	(197,000)
Separation expenses	(21,940,000)	(23,208,000)	(24,166,000)
Reimbursed Expenses	(5,215,000)	(7,063,000)	(6,208,000)
General and administrative expenses	(29,672,000)	(28,154,000)	(32,515,000)
Other expenses		(488,000)	(129,134,000)
Gains (Losses) on Extinguishment of Debt		(94,000)	(74,000)
Impairment loss	(11,373,000)	(8,389,000)	(8,512,000)
Dividends, Preferred Stock	(12,664,000)	(12,907,000)	(12,907,000)
Funds from operations available to common stockholders	77,134,000	66,492,000	(76,875,000)
Real estate depreciation and amortization, including Company's share of joint ventures	(92,041,000)	(62,043,000)	(62,710,000)
Impairment loss on depreciable investment property, net of amounts attributable to noncontrolling interests		(11,748,000)	(7,632,000)
Gain on sale of depreciated investment properties including Company's share of joint ventures	127,401,000	41,944,000	5,885,000
Noncontrolling Interest Related to Gain on Sale of Depreciated Investment Properties	(3,397,000)
NET INCOME (LOSS) AVAILABLE TO COMMON STOCKHOLDERS	109,097,000	32,821,000	(141,332,000)
Total Assets	$ 2,273,206,000	$ 1,124,242,000	$ 1,235,535,000