Note 13 - Tax Monetization Transactions (Details Textual) - USD ($) $ in Thousands								12 Months Ended			72 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 23, 2022	Oct. 25, 2021	Aug. 14, 2019	May 17, 2018	Dec. 16, 2016	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2022
Proceeds from Noncontrolling Interests								$ 5,443	$ 5,390	$ 7,577
JPM Capital Corporation [Member]
Proceeds from Noncontrolling Interests											$ 15,300
JPM Capital Corporation [Member] | Forecast [Member]
Proceeds from Noncontrolling Interests	$ 2,000
DAC 2 [Member]
Percentage Of Ownership Interests							63.25%
Other Geothermal Power Plants [Member]
Percentage Of Ownership Interests							100.00%
OPC LLC [Member] | JPM Capital Corporation [Member] | Capital Unit, Class B [Member]
Fair Value of Equity Interest Sold							$ 3,000
Tungsten Mountain [Member]
Partnership Agreement, Initial Purchase Price						$ 33,400
Partnership Agreement, Expected Additional Installments						$ 13,000
Partnership Agreement, Percentage of Distributable Cash Flow Generated						97.50%
Partnership Agreement, Percentage of Taxable Income						95.00%
Partnership Agreement, Percentage of Distributable Cash Flow Generated to Private Investor if Target Return Not Reached						100.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached						99.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached, No Longer Generating PTCs						5.00%
McGinness Plant [Member]
Partnership Agreement, Initial Purchase Price					$ 59,300
Partnership Agreement, Expected Additional Installments					$ 9,000
Partnership Agreement, Percentage of Distributable Cash Flow Generated					97.50%
Partnership Agreement, Percentage of Taxable Income					95.00%
Partnership Agreement, Percentage of Distributable Cash Flow Generated to Private Investor if Target Return Not Reached					100.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached					99.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached, No Longer Generating PTCs					5.00%
McGinness Plant [Member] | Maximum [Member]
Partnership Agreement, Expected Additional Installments					$ 22,000
Mammoth Complex [Member] | CD4 Geothermal Power Plant [Member]
Partnership Agreement, Initial Purchase Price			$ 50,300
Partnership Agreement, Expected Additional Installments			$ 7,300
Partnership Agreement, Percentage of Tax Attributes Attributable to Investor			99.00%
Partnership Agreement, Percentage of Distributable Cash Flow Generated			97.50%
Partnership Agreement, Percentage of Taxable Income			95.00%
Partnership Agreement, Percentage of Distributable Cash Flow Generated to Private Investor if Target Return Not Reached			75.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached			99.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached, No Longer Generating PTCs			5.00%
Partnership Agreement, Initial Purchase Price, Allocated to Noncontrolling Interest			$ 3,900
Partnership Agreement, Initial Purchase Price, Allocated to Tax Benefits			$ 46,400
Ormat Nevada Inc. [Member] | Steamboat Hills Repower Geothermal Power Plant [Member]
Partnership Agreement, Initial Purchase Price				$ 38,900
Partnership Agreement, Expected Additional Installments				$ 5,300
Partnership Agreement, Percentage of Distributable Cash Flow Generated				97.50%
Partnership Agreement, Percentage of Taxable Income				95.00%
Partnership Agreement, Percentage of Distributable Cash Flow Generated to Private Investor if Target Return Not Reached				100.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached				99.00%
Partnership Agreement, Percentage of Taxable Income to Private Investor if Target Return Not Reached, No Longer Generating PTCs				5.00%
Opal Geo LLC [Member]
Percentage Of Distributable Cash to Controlling Interest							97.50%
Percentage of Income (Loss), Gain, Deduction and Credit Allocated to Controlling Interests		95.00%					1.00%
Percentage of Income (Loss), Gain, Deduction and Credit Allocated to Controlling Interests, PTCs Not Available							95.00%
Opal Geo LLC [Member] | Capital Unit, Class A [Member]
Percentage Of Ownership Interests							100.00%
Opal Geo LLC [Member] | JPM Capital Corporation [Member]
Proceeds from Noncontrolling Interests							$ 62,100
Percentage Of Distributable Cash to Nontrolling Interests		100.00%					2.50%
Percentage of Income (Loss), Gain, Deduction and Credit Allocated to Noncontrolling Interests		5.00%					99.00%
Percentage of Income (Loss), Gain, Deduction and Credit Allocated to Noncontrolling Interests, PTCs Not Available							5.00%
Opal Geo LLC [Member] | JPM Capital Corporation [Member] | Capital Unit, Class B [Member]
Percentage of Equity Interest Sold							100.00%