Note 7 - Variable Interest Entities - Assets and Liabilities for the Company's 2015 Variable Interest Entity (Details) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restricted cash and cash equivalents (primarily related to VIEs)		$ 104,166	$ 88,526
Property, plant and equipment, net		2,294,973	2,099,046
Construction-in-process		721,483	479,315
Total assets	[1],[2]	4,425,678	3,888,987	$ 3,250,494
Accounts payable and accrued expenses		143,186	152,763
Long-term debt		1,925,530
Other long-term liabilities		4,951	6,235
Total liabilities		2,417,888	1,937,720
Assets:
Restricted cash and cash equivalents		104,166	88,526	81,937
Property, plant and equipment, net		2,294,973	2,099,046
Construction-in-process		721,483	479,315
Total assets	[1],[2]	4,425,678	3,888,987	$ 3,250,494
Liabilities:
Accounts payable and accrued expenses		143,186	152,763
Long-term debt		1,925,530
Other long-term liabilities		4,951	6,235
Total liabilities		2,417,888	1,937,720
Variable Interest Entity, Primary Beneficiary [Member]
Construction-in-process		366,924	198,812
Assets:
Construction-in-process		366,924	198,812
Variable Interest Entity, Primary Beneficiary [Member] | Project Debt [Member]
Restricted cash and cash equivalents (primarily related to VIEs)		101,364
Other current assets		122,944	133,017
Property, plant and equipment, net		1,300,941	1,208,165
Construction-in-process		96,764	27,440
Other long-term assets		326,686	156,000
Total assets		1,948,699	1,611,203
Accounts payable and accrued expenses		34,155	21,958
Long-term debt		672,804	730,177
Other long-term liabilities		419,085	143,985
Total liabilities		1,126,044	896,120
Assets:
Restricted cash and cash equivalents			86,581
Other current assets		122,944	133,017
Property, plant and equipment, net		1,300,941	1,208,165
Construction-in-process		96,764	27,440
Other long-term assets		326,686	156,000
Total assets		1,948,699	1,611,203
Liabilities:
Accounts payable and accrued expenses		34,155	21,958
Long-term debt		672,804	730,177
Other long-term liabilities		419,085	143,985
Total liabilities		1,126,044	896,120
Variable Interest Entity, Primary Beneficiary [Member] | Power Purchase Agreement [Member]
Restricted cash and cash equivalents (primarily related to VIEs)		0
Other current assets		31,781	30,917
Property, plant and equipment, net		858,755	770,055
Construction-in-process		270,160	171,372
Other long-term assets		55,441	60,143
Total assets		1,216,137	1,032,487
Accounts payable and accrued expenses		10,004	15,362
Long-term debt		2,444	0
Other long-term liabilities		49,919	39,486
Total liabilities		62,367	54,848
Assets:
Restricted cash and cash equivalents			0
Other current assets		31,781	30,917
Property, plant and equipment, net		858,755	770,055
Construction-in-process		270,160	171,372
Other long-term assets		55,441	60,143
Total assets		1,216,137	1,032,487
Liabilities:
Accounts payable and accrued expenses		10,004	15,362
Long-term debt		2,444	0
Other long-term liabilities		49,919	39,486
Total liabilities		$ 62,367	$ 54,848

[1] Electricity segment assets include goodwill in the amount of $85.3 million, $20.5 million and $20.1 million as of December 31, 2021, 2020 and 2019, respectively, $65.4 million of which was added in the third quarter of 2021 as a result of the Terra-Gen Transaction as further described under Note 2 to the consolidated financial statements. Energy Storage segment assets include goodwill in the amount of $4.6 million, $4.1 million and $0.0 million as of December 31, 2021, 2020 and 2019, respectively. No goodwill is included in the Product segment assets as of December 31, 2021, 2020 and 2019.

[2] Including unconsolidated investments