Note 5 - Investments In and Advances to Real Estate Joint Ventures (Details Textual) $ in Thousands		1 Months Ended	9 Months Ended
		Oct. 31, 2021 USD ($)	Sep. 30, 2021 USD ($) ft²	Sep. 30, 2020 USD ($)	Aug. 03, 2021 USD ($)	Dec. 31, 2020 ft²
Gross Leasable Area (Square Foot) | ft²	[1]		1,435
Payments to Acquire Interest in Joint Venture			$ 7,546	$ 14,640
Weingarten Realty Investors [Member]
Secured Debt Assumed by Joint Ventures in Business Combination, Including Fair Market Value Adjustment					$ 191,500
Secured Debt Assumed by Joint Ventures in Business Combination, Fair Market Value Adjustment					800
Subsequent Event [Member]
Joint Venture, Ownership, Purchased, Percent		70.00%
Joint Venture, Number of Property Interests		6
Payments to Acquire Interest in Joint Venture		$ 425,800
Ownership Interest in Joint Venture, Percentage		100.00%
Proceeds from Divestiture of Interest in Consolidated Subsidiaries		$ 425,800
All Equity Method Investments [Member]
Number of Real Estate Properties			125			97
Gross Leasable Area (Square Foot) | ft²			25,300,000			21,200,000
Unconsolidated Joint Ventures Acquired in Weingarten Merger [Member]
Number of Real Estate Properties			30
Gross Leasable Area (Square Foot) | ft²			4,400,000
Number of Joint Ventures			9
Joint Ventures, Fair Market Value					$ 586,200
Real Estate Joint Ventures [Member] | Operating Properties [Member]
Number of Real Estate Properties, Interest Disposed of or Transferred			2
Equity Method Investment, Sales Price			$ 53,700
Equity Method Investment, Realized Gain (Loss) on Disposal, Total			$ 4,200

[1] Gross leasable area ("GLA")