Document And Entity Information - USD ($)	Dec. 31, 2019	Feb. 26, 2020	Jun. 30, 2019
Document Information [Line Items]
Entity, Registrant Name	ORMAT TECHNOLOGIES, INC.
Current Fiscal Year End Date	--12-31
Document, Fiscal Period Focus	FY
Document, Fiscal Year Focus	2019
Document, Type	10-K/A
Document, Annual Report	true
Document, Period End Date	Dec. 31, 2019
Document, Transition Report	false
Entity, File Number	001-32347
Entity, Incorporation, State or Country Code	DE
Entity, Tax Identification Number	88-0326081
Entity, Address, Address Line One	6140 Plumas Street
Entity, Address, City or Town	Reno
Entity, Address, State or Province	NV
Entity, Address, Postal Zip Code	89519-6075
City Area Code	775
Local Phone Number	356-9029
Title of 12(b) Security	Common Stock $0.001 Par Value
Trading Symbol	ORA
Security Exchange Name	NYSE
Entity, Well-known Seasoned Issuer	Yes
Entity, Voluntary Filers	No
Entity, Current Reporting Status	Yes
Entity, Interactive Data, Current	Yes
Entity, Filer Category	Large Accelerated Filer
Entity, Small Business	false
Entity, Emerging Growth Company	false
Entity, Shell Company	false
Entity, Public Float			$ 2,527,613,074
Entity, Common Stock Shares, Outstanding		51,031,652
Amendment Description	This Amendment No. 1 on Form 10-K/A (“Amendment No. 1”) amends our Annual Report on Form 10-K for the fiscal year ended December 31, 2019 (“Original Filing”), filed with the U.S. Securities and Exchange Commission (“SEC”) on March 2, 2020 (“Original Filing Date”). Amendment No. 1 is being made to include Exhibit 4.6, the Description of Securities Registered under Section 12 of the Securities Exchange Act of 1934, which was inadvertently omitted from the Original Filing. In addition, we have revised the cover page of the Original Filing with respect to our status as a well-known seasoned issuer.   Except as described above, no changes have been made to the Original Filing and this Amendment No. 1 does not modify, amend or update in any way any of the financial or other information contained in the Original Filing. This Amendment No. 1 does not reflect events that may have occurred subsequent to the Original Filing Date.   In addition, as required by Rule 12b-15 under the Securities Exchange Act of 1934, as amended, new certifications pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 are filed as exhibits to this Amendment No. 1 under Item 15 of Part IV hereof. Because no financial statements have been included in this Amendment No. 1 and this Amendment No. 1 does not contain or amend any disclosure with respect to Items 307 and 308 of Regulation S-K, paragraphs 3, 4, and 5 of the certifications have been omitted.
Amendment Flag	true
Entity, Central Index Key	0001296445