The amount of current power generation during the period.

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The term of a non-recourse financing agreement.

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The amount of a non-recourse financing agreement.

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- Definition

The initial purchase price of the power plant that sold to a private investor by the company.

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The amount of additional installments that are expected to be paid by the buyer pursuant to the partnership agreement.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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No definition available.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Note 12 - Subsequent Events (Details Textual) $ / shares in Units, $ in Thousands				3 Months Ended
	May 07, 2018 USD ($) $ / shares	Apr. 30, 2018 USD ($) MWh	Apr. 24, 2018 USD ($) MWh	Mar. 31, 2018 USD ($) $ / shares	Mar. 31, 2017 USD ($) $ / shares	May 17, 2018 USD ($)	May 03, 2018 USD ($)	Dec. 31, 2017 USD ($)
Dividends, Common Stock, Total				$ 11,640	$ 8,448
Common Stock, Dividends, Per Share, Declared \| $ / shares				$ 0.23	$ 0.17
Property, Plant and Equipment, Net, Ending Balance				$ 1,723,560				$ 1,734,691
Subsequent Event [Member]
Dividends, Common Stock, Total	$ 5,100
Common Stock, Dividends, Per Share, Declared \| $ / shares	$ 0.10
Dividends Payable, Date of Record	May 21, 2018
Dividends Payable, Date to be Paid	May 30, 2018
Subsequent Event [Member] \| U.S. Geothermal [Member]
Current Power Generation \| MWh			38
Payments to Acquire Businesses, Gross			$ 110,000
Subsequent Event [Member] \| U.S. Geothermal [Member] \| Ormat Nevada Inc. [Member]
Payments to Acquire Businesses, Gross			106,000
Subsequent Event [Member] \| U.S. Geothermal [Member] \| Ormat Technologies, Inc. [Member]
Payments to Acquire Businesses, Gross			$ 4,000
Subsequent Event [Member] \| Puna Geothermal Power Plant [Member]
Property, Plant and Equipment, Net, Ending Balance							$ 109,000
Subsequent Event [Member] \| Platanares [Member]
Non-recourse Financing Agreement		$ 124,700
Current Power Generation \| MWh		35
Non-recourse Finacing Agreement, Term		14 years
Subsequent Event [Member] \| Platanares [Member] \| Minimum [Member]
Debt Instrument, Interest Rate, Stated Percentage		6.75%
Subsequent Event [Member] \| Platanares [Member] \| Maximum [Member]
Debt Instrument, Interest Rate, Stated Percentage		7.25%
Subsequent Event [Member] \| Tungsten Mountain [Member]
Parternship Agreement, Initial Purchase Price						$ 33,400
Partnership Agreement, Expected Additional Installments						$ 13,000