Represents fair value of projects under construction acquired in a business combination.

No definition available.

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- Definition

Construction in progress costs incurred.

+ References

No definition available.

+ Details

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- Definition

Represents construction in progress costs write off.

+ References

No definition available.

+ Details

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- Definition

Transfer of construction in progress to property plant and equipment.

+ References

No definition available.

+ Details

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Namespace Prefix:	ora_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Transfer of projects under exploration and development to projects under construction.

+ References

No definition available.

+ Details

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Namespace Prefix:	ora_
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Balance Type:	credit
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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The adjustment to expense previously capitalized costs of drilling exploratory wells when proved reserves are not found or when the entity obtains information that raises substantial doubt about the economic or operational viability of the project.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6475089&loc=d3e66610-109467

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 40
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-URI http://asc.fasb.org/extlink&oid=6475089&loc=d3e66625-109467

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 932
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-Section 40
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-URI http://asc.fasb.org/extlink&oid=6475089&loc=d3e66584-109467

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 35
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66906256&loc=d3e66150-109466

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Balance Type:	credit
Period Type:	duration

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Note 8 - Property, Plant and Equipment and Construction-in-process - Activity in Construction and Development (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Balance				$ 261,690					$ 261,690
Write off of unsuccessful exploration costs	$ 0	$ 0	$ 0	0	$ (3)	$ 0	$ 0	$ (123)	0	$ (126)	$ (1,796)
Balance	376,555				261,690				376,555	261,690
Projects Under Exploration and Development [Member]
Balance				70,958				63,875	70,958	63,875	54,447
Cost incurred during the year									17,215	7,209	11,224
Write off of unsuccessful exploration costs										(126)	(1,796)
Transfer of projects under exploration and development to projects under construction									(3,536)
Balance	84,637				70,958				84,637	70,958	63,875
Projects Under Exploration and Development [Member] \| Up-front Bonus Lease Costs [Member]
Balance				17,018				17,018	17,018	17,018	17,385
Cost incurred during the year									0	0	0
Write off of unsuccessful exploration costs										0	(367)
Transfer of projects under exploration and development to projects under construction									0
Balance	17,018				17,018				17,018	17,018	17,018
Projects Under Exploration and Development [Member] \| Exploration and Development Costs [Member]
Balance				53,237				46,154	53,237	46,154	36,359
Cost incurred during the year									17,215	7,209	11,224
Write off of unsuccessful exploration costs										(126)	(1,429)
Transfer of projects under exploration and development to projects under construction									(3,536)
Balance	66,916				53,237				66,916	53,237	46,154
Projects Under Exploration and Development [Member] \| Interest Capitalized [Member]
Balance				703				703	703	703	703
Cost incurred during the year									0	0	0
Write off of unsuccessful exploration costs										0	0
Transfer of projects under exploration and development to projects under construction									0
Balance	703				703				703	703	703
Construction in Progress [Member]
Balance				190,732				229,667	190,732	229,667	252,262
Cost incurred during the year									267,237	219,610	239,226
Transfer of projects under exploration and development to projects under construction									3,536
Balance	291,918				190,732				291,918	190,732	229,667
Transfer of completed projects to property, plant and equipment									(134,152)	(261,833)	(261,821)
Cost write off										(1,380)
Fair value of projects under construction acquired in a business combination										4,668
Insurance recoveries									(35,435)
Construction in Progress [Member] \| Up-front Bonus Lease Costs [Member]
Balance				27,473				27,473	27,473	27,473	37,713
Cost incurred during the year									0	0	0
Transfer of projects under exploration and development to projects under construction									0
Balance	27,473				27,473				27,473	27,473	27,473
Transfer of completed projects to property, plant and equipment									0	0	(10,240)
Cost write off										0
Fair value of projects under construction acquired in a business combination										0
Insurance recoveries									0
Construction in Progress [Member] \| Drilling And Construction Costs [Member]
Balance				160,398				198,943	160,398	198,943	202,211
Cost incurred during the year									264,137	219,610	231,926
Transfer of projects under exploration and development to projects under construction									3,536
Balance	258,484				160,398				258,484	160,398	198,943
Transfer of completed projects to property, plant and equipment									(134,152)	(261,443)	(235,194)
Cost write off										(1,380)
Fair value of projects under construction acquired in a business combination										4,668
Insurance recoveries									(35,435)
Construction in Progress [Member] \| Interest Capitalized [Member]
Balance				$ 2,861				$ 3,251	2,861	3,251	12,338
Cost incurred during the year									3,100	0	7,300
Transfer of projects under exploration and development to projects under construction									0
Balance	$ 5,961				$ 2,861				5,961	2,861	3,251
Transfer of completed projects to property, plant and equipment									0	(390)	$ (16,387)
Cost write off										0
Fair value of projects under construction acquired in a business combination										$ 0
Insurance recoveries									$ 0