Note 8 - Other Investments (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Equity Method Investments	$ 1,000,000	$ 590,700
Secured Debt, Total	448,652	311,272
Preferred Equity Investments [Member]
Equity Method Investments	$ 98,700	$ 98,200
Number of Real Estate Properties	39	113
Income (Loss) from Equity Method Investments, Total	$ 21,400	$ 28,400
Equity Method Investment, Realized Gain (Loss) on Disposal, Total	8,600	13,700
Payments to Acquire Equity Method Investments	60,700
Secured Debt, Total	237,400
Long-term Debt, Fair Value	$ 3,300
Preferred Equity Investments [Member] | Minimum [Member]
Debt Instrument, Term (Month)	2 months
Debt Instrument, Interest Rate, Stated Percentage	4.19%
Preferred Equity Investments [Member] | Maximum [Member]
Debt Instrument, Term (Month)	2 years 6 months
Debt Instrument, Interest Rate, Stated Percentage	8.88%
Preferred Equity Investments [Member] | San Antonio, Texas [Member]
Payments to Acquire Equity Method Investments	$ 54,900
Preferred Equity Investments [Member] | Property in Queens, NY [Member]
Payments to Acquire Equity Method Investments		$ 10,000
Preferred Equity Investments [Member] | Leased Properties [Member]
Number of Real Estate Properties	28	103