Note 5 - Other Investments (Details Textual) - Preferred Equity Investments [Member] $ in Millions	6 Months Ended
Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)
Equity Method Investments	$ 69.9
Number of Real Estate Properties	16
Income (Loss) from Equity Method Investments	$ 8.1	$ 7.7

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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