Depreciation of cash grant rendered by an entity during the reporting period.

No definition available.

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- Details

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- Definition

Term of the power purchase agreement.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets, including cash grants, used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

No definition available.

+ Details

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets, including construction-in-progress, used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The term of the Company's property, plant and equipment operating period.

+ References

No definition available.

+ Details

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- Definition

The percent of revenue for annual royalty payments.

+ References

No definition available.

+ Details

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Namespace Prefix:	ora_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Item represents the gross sales price of a disposition.

+ References

No definition available.

+ Details

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Namespace Prefix:	ora_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.14)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

-Article 5

+ Details

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Balance Type:	credit
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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The gains and losses included in earning resulting from the sale of a project.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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Data Type:	na
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- Details

Name:	dei_LegalEntityAxis=ora_OrzunilIDeElectricidadLimitadaMember
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- Details

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Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) (USD $)	12 Months Ended			1 Months Ended	3 Months Ended		0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 26, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 02, 2013
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Depreciation	$ 87,851,000us-gaap_Depreciation	$ 91,791,000us-gaap_Depreciation	$ 89,876,000us-gaap_Depreciation
Depreciation, Net of Amortization of Cash Grant	5,318,000	4,330,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	688,916,000	601,065,000
Property Plant and Equipment Including Construction-in-Progress, Net	1,327,356,000	1,316,597,000
Property, Plant and Equipment, Cash Grant, Net	149,785,000	127,675,000
Heber Solar Project [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Sales Price of Disposition				35,250,000
Proceeds from Sales of Business, Affiliate and Productive Assets					20,250,000	15,000,000
Gain (Loss) on Sale of Project					7,600,000
Power Plants [Member] \| KENYA
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Property Plant and Equipment Including Construction-in-Progress, Net	305,129,000	338,517,000
Kenya Power And Lighting Co Limited [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Power Purchase Agreements Term	20 years
Zunil Power Plant [Member] \| Nacional de Electrificacion (INDE) [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	3.00%
Foreign Countries [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Property Plant and Equipment Including Construction-in-Progress, Net	407,003,000	424,567,000
Momotombo Power Plant [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment		35,396,000
Orzunil I de Electricidad, Limitada [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Property Plant and Equipment Including Construction-in-Progress, Net	19,141,000	18,846,000
Ortitlan, Limitada [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Property Plant and Equipment Including Construction-in-Progress, Net	45,624,000	52,272,000
Ormat International [Member]
Note 7 - Property, Plant and Equipment and Construction-in-Process (Details) [Line Items]
Property Plant and Equipment Including Construction-in-Progress, Net	$ 12,300,000
Royalty Rate							12.00%
Property, Plant and Equipment Operating Period							15 years