Note 10 - Commitments and Contingencies (Details Textual) - USD ($) $ in Millions	Mar. 03, 2021	Mar. 29, 2016
Former Local Sales Representative vs. Ormat [Member] \| Pending Litigation [Member]
Loss Contingency, Damages Sought, Value		$ 4.6
Loss Contingency, Additional Damages Sought for Ormat Geothermal Products Sales in Chile, Percent		3.75%
Loss Contingency, Damages Sought, Ormat Geothermal Products Sales in Chile, Period (Year)		10 years
Avishai Shmuel Mano vs. Ormat [Member]
Loss Contingency, Damages Sought, Value	$ 100.0

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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