Note 2 - Operating Property Activities (Details) - Acquisition of Operating Properties $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($) ft²
Business Acquisition [Line Items]
Cash	$ 618,244	[1]
Debt Assumed	688,087
Other	248,413
Total	$ 1,554,744
GLA (in Square Feet) | ft²	6,292	[2]
Elmont Plaza [Member]
Business Acquisition [Line Items]
Cash	$ 2,400	[1],[3]
Debt Assumed		[3]
Other	$ 3,358	[3]
Total	$ 5,758	[3]
GLA (in Square Feet) | ft²	13	[2],[3]
Garden State Pavilions [Member]
Business Acquisition [Line Items]
Cash	$ 16,300	[1]
Total	$ 16,300
GLA (in Square Feet) | ft²	111	[2]
Kimstone [Member]
Business Acquisition [Line Items]
Cash	$ 513,513	[1],[4]
Debt Assumed	637,976	[4]
Other	236,011	[4]
Total	$ 1,387,500	[4]
GLA (in Square Feet) | ft²	5,631	[2],[4]
Copperfield Village [Member]
Business Acquisition [Line Items]
Cash	$ 18,700	[1]
Debt Assumed	20,800
Total	$ 39,500
GLA (in Square Feet) | ft²	165	[2]
Snowden Square [Member]
Business Acquisition [Line Items]
Cash	$ 4,868	[1]
Total	$ 4,868
GLA (in Square Feet) | ft²	25	[2]
Dulles Town Crossing [Member]
Business Acquisition [Line Items]
Cash	$ 4,830	[1]
Total	$ 4,830
GLA (in Square Feet) | ft²	9	[2]
Flagler Park [Member]
Business Acquisition [Line Items]
Cash	$ 1,875	[1]
Total	$ 1,875
GLA (in Square Feet) | ft²	5	[2]
West Farms Parcel [Member]
Business Acquisition [Line Items]
Cash	$ 6,200	[1]
Total	$ 6,200
GLA (in Square Feet) | ft²	24	[2]
Milleridge Inn [Member]
Business Acquisition [Line Items]
Cash	$ 7,500	[1]
Total	$ 7,500
GLA (in Square Feet) | ft²		[2]
Woodgrove Festival Parcels [Member]
Business Acquisition [Line Items]
Cash	$ 5,611	[1]
Total	$ 5,611
GLA (in Square Feet) | ft²	12	[2]
Montgomery Plaza [Member]
Business Acquisition [Line Items]
Cash	$ 34,522	[1],[5]
Debt Assumed	29,311	[5]
Other	9,044	[5]
Total	$ 72,877	[5]
GLA (in Square Feet) | ft²	291	[2],[5]
The 125 Coulter Avenue Parcel [Member]
Business Acquisition [Line Items]
Cash	$ 1,925	[1]
Total	$ 1,925
GLA (in Square Feet) | ft²	6	[2]

[1] The Company utilized $39.8 million associated with Internal Revenue Code 1031 sales proceeds.

[2] Gross leasable area ("GLA")

[3] The Company acquired from its partner the remaining ownership interest in a property that was held in a joint venture in which the Company had a 50.0%noncontrolling interest. The Company evaluated this transaction pursuant to the FASB's Consolidation guidance and as a result, recognized a loss on change in control of interest of $0.2 million resulting from the fair value adjustment associated with the Company's previously held equity interest, which is reflected in the purchase price above in Other.

[4] The Company acquired from its partner the remaining ownership interest in 39 properties that were held in a joint venture in which the Company had a 33.3%noncontrolling interest. The Company evaluated this transaction pursuant to the FASB's Consolidation guidance and as a result, recognized a gain on change in control of interest of $140.0 million resulting from the fair value adjustment associated with the Company's previously held equity interest, which is reflected in the purchase price above in Other.

[5] The Company acquired from its partner the remaining ownership interest in a property that was held in a joint venture in which the Company had a 20.0%noncontrolling interest. The Company evaluated this transaction pursuant to the FASB's Consolidation guidance and as a result, recognized a gain on change in control of interest of $6.3 million resulting from the fair value adjustment associated with the Company's previously held equity interest, which is reflected in the purchase price above in Other.