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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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

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Face (par) amount of debt instrument at time of issuance.

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

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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

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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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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 24 - Subsequent Events (Details Textual) $ / shares in Units, $ in Thousands, ₪ in Millions									12 Months Ended
	May 21, 2018 USD ($)	May 21, 2018 ILS (₪)	May 07, 2018 USD ($) $ / shares	Apr. 30, 2018 USD ($) MWh	Apr. 24, 2018 USD ($)	Mar. 22, 2018 USD ($)	Mar. 01, 2018 USD ($) $ / shares	Jan. 24, 2018 USD ($) MWh $ / shares	Dec. 31, 2017 USD ($) $ / shares	Dec. 31, 2016 USD ($) $ / shares	Dec. 31, 2015 USD ($) $ / shares	May 17, 2018 USD ($)	May 03, 2018 USD ($)
Dividends, Common Stock, Total									$ 20,511	$ 25,682	$ 12,716
Common Stock, Dividends, Per Share, Declared \| $ / shares									$ 0.41	$ 0.52	$ 0.26
Property, Plant and Equipment, Net, Ending Balance									$ 1,734,691	$ 1,556,378
Subsequent Event [Member]
Dividends, Common Stock, Total			$ 5,100				$ 11,500
Common Stock, Dividends, Per Share, Declared \| $ / shares			$ 0.10				$ 0.23
Dividends Payable, Date of Record			May 21, 2018				Mar. 14, 2018
Dividends Payable, Date to be Paid			May 30, 2018				Mar. 29, 2018
Subsequent Event [Member] \| Platanares [Member]
Non-recourse Finacing Agreement, Term				14 years
Subsequent Event [Member] \| Migdal Loan [Member]
Debt Instrument, Interest Rate, Stated Percentage						4.80%
Debt Instrument, Face Amount						$ 100,000
Debt Instrument, Periodic Payment, Total						4,200
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid						$ 37,000
Debt Instrument Increase in Stated Interest Rate if Rating is Downgraded to ILA Negative						0.50%
Debt Instrument Increase in Stated Interest Rate Each Additional Downgrade						0.25%
Debt Instrument Decrease in Stated Interest Rate for Each Rating Upgrade						0.25%
Debt to EBITDA Ratio Threshold for Rate Increase						4.5
Debt Instrument Increase in Stated Interest Rate if Debt to EBITDA Ratio Exceeds Threshold						0.50%
Debt to EBITDA Ratio Requirement						6
Stockholders Equity, Debt Covenant, Minimum Threshold						$ 650,000
Stockholders Equity to Total Assets, Ratio						25.00%
Stockholders Equity, Debt Covenant, Minimum Threshold to Pay Dividends						$ 800,000
Dividends to Net Income, Ratio						50.00%
Subsequent Event [Member] \| Migdal Loan [Member] \| Minimum [Member]
Debt Instrument, Interest Rate, Stated Percentage						4.80%
Subsequent Event [Member] \| Migdal Loan [Member] \| Maximum [Member]
Debt Instrument, Increase in Stated Interest Rate						1.00%
Subsequent Event [Member] \| Platanares [Member]
Current Power Generation \| MWh				35
Non-recourse Financing Agreement				$ 124,700
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
Subsequent Event [Member] \| Puna Geothermal Power Plant [Member]
Property, Plant and Equipment, Net, Ending Balance													$ 109,000
Subsequent Event [Member] \| Heit vs Ormat Technologies, Inc. [Member]
Loss Contingency, Damages Sought, Value	$ 26,000	₪ 93
Subsequent Event [Member] \| U.S. Geothermal [Member]
Expected Power Generating Capacity \| MWh								45
Current Power Generation \| MWh								38
Subsequent Event [Member] \| U.S. Geothermal [Member]
Business Acquisition, Share Price \| $ / shares								$ 5.45
Business Combination, Consideration Transferred, Total								$ 109,900
Payments to Acquire Businesses, Gross					$ 110,000
Payments to Settle Outstanding In-the-money Options by Acquiree					4,000
Subsequent Event [Member] \| U.S. Geothermal [Member] \| Ormat Nevada Inc. [Member]
Payments to Acquire Businesses, Gross					$ 106,000