Note 11 - Investments in Affiliates (Details Textual) $ in Thousands	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Assets	$ 2,077,387	$ 2,167,933
Real Estate Entities [Member]
Number of Entities	2
Real Estate Entities [Member] | Minimum [Member]
Equity Method Investment, Ownership Percentage	10.00%
Real Estate Entities [Member] | Maximum [Member]
Equity Method Investment, Ownership Percentage	25.00%
Foreign Affiliates [Member] | Minimum [Member]
Equity Method Investment, Ownership Percentage	25.00%
Foreign Affiliates [Member] | Maximum [Member]
Equity Method Investment, Ownership Percentage	50.00%
Real Estate Entities [Member]
Assets	$ 373,500
Real Estate Entities One [Member]
Assets	73,300
Foreign Affiliates [Member]
Assets	269,700
Asphalt Terminal Entity [Member]
Assets	30,500
Real Estate Entities Two [Member]
Assets	$ 73,300