Note 8 - Other Real Estate Investments (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Equity Method Investments	$ 590,700	$ 578,100
Secured Debt, Total	311,272	484,008
Preferred Equity Investments [Member]
Equity Method Investments	$ 98,200	$ 175,300
Number of Real Estate Properties	113	240
Income (Loss) from Equity Method Investments, Total	$ 28,400	$ 25,800
Equity Method Investment, Realized Gain (Loss) on Disposal, Total	$ 13,700	$ 7,300
Preferred Equity Investments [Member] \| Minimum [Member]
Debt Instrument, Term (Month)	1 month
Debt Instrument, Interest Rate, Stated Percentage	4.19%
Preferred Equity Investments [Member] \| Maximum [Member]
Debt Instrument, Term (Month)	4 years
Debt Instrument, Interest Rate, Stated Percentage	9.85%
Preferred Equity Investments [Member] \| Leased Properties [Member]
Number of Real Estate Properties	103	230
Preferred Equity Investment [Member]
Secured Debt, Total	$ 141,900
Long-term Debt, Fair Value	4,800
Preferred Equity Investment [Member] \| Property in Queens, NY [Member]
Equity Method Investments	$ 10,100
Equity Method Investment, Ownership Percentage	71.43%

Contractual interest rate for funds borrowed, under the debt agreement.

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