Note 12 - Investments in Affiliates (Details Textual) $ in Thousands	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Jun. 30, 2021 USD ($)
Assets, Total	$ 2,291,332	$ 2,494,927	$ 2,478,898
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%
Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member]
Assets, Total	$ 110,501	$ 113,203	$ 101,457
Real Estate Entities One [Member]
Assets, Total	77,400
Asphalt Terminal Entity [Member]
Assets, Total	$ 33,100