Note 8 - Property, Plant and Equipment and Construction-in-process - Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, plant and equipment	$ 4,883,933	$ 4,183,029
Asset retirement cost	59,123	48,578
Less accumulated depreciation	(1,884,984)	(1,689,572)
Property, plant and equipment, net	2,998,949	2,493,457
Land [Member]
Property, plant and equipment	47,612	42,335
Leasehold Improvements [Member]
Property, plant and equipment	12,588	13,230
Machinery and Equipment [Member]
Property, plant and equipment	341,931	350,584
Office Equipment [Member]
Property, plant and equipment	127,970	52,222
Vehicles [Member]
Property, plant and equipment	17,097	14,115
Energy Equipment [Member]
Property, plant and equipment	158,604	91,025
Solar Facility Equipment [Member]
Property, plant and equipment	59,214	32,003
Geothermal And Recovered Energy Generation Power Plants [Member] | UNITED STATES
Property, plant and equipment	3,191,505	2,641,280
Geothermal And Recovered Energy Generation Power Plants [Member] | Foreign Countries [Member]
Property, plant and equipment	$ 868,289	$ 897,657