Note 5 - Investments in and Advances to Real Estate Joint Ventures - Joint Venture Investments Accounted for Under the Equity Method, Debt Details (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2024	Dec. 31, 2023
Mortgage and notes payable		$ 1,480.4	$ 1,248.9
Prudential Investment Program [Member]
Mortgage and notes payable		$ 270.9	$ 291.6
Weighted average interest rate		5.91%	6.00%
Weighted average remaining term (Month)	[1]	21 months 12 days	24 months 18 days
KIR [Member]
Mortgage and notes payable		$ 273.5	$ 273.4
Weighted average interest rate		5.82%	5.82%
Weighted average remaining term (Month)	[1]	36 months 6 days	39 months 6 days
R2G Venture LLC [Member]
Mortgage and notes payable	[2]	$ 67.2	$ 0.0
Weighted average interest rate	[2]	2.90%	0.00%
Weighted average remaining term (Month)	[1],[2]	83 years 8 months 12 days
CPP [Member]
Mortgage and notes payable		$ 81.6	$ 81.9
Weighted average interest rate		5.12%	5.12%
Weighted average remaining term (Month)	[1]	28 months	31 months
Other Institutional Joint Ventures [Member]
Mortgage and notes payable		$ 234.3	$ 234.1
Weighted average interest rate		5.76%	5.76%
Weighted average remaining term (Month)	[1]	32 months 21 days	35 months 21 days
Other Joint Venture Programs [Member]
Mortgage and notes payable	[3]	$ 552.9	$ 367.9
Weighted average interest rate	[3]	5.01%	4.44%
Weighted average remaining term (Month)	[1],[3]	47 months 27 days	59 months 18 days

[1] Includes extension options

[2] In connection with the RPT Merger the Company acquired an ownership interest in this joint venture, which had aggregate secured debt of $66.7 million (including a fair market value adjustment of $14.4 million).

[3] In connection with the RPT Merger the Company acquired an ownership interest in a joint venture, which had aggregate secured debt of $187.1 million (including a fair market value adjustment of $3.2 million).