Note 11 - Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended	9 Months Ended					9 Months Ended				12 Months Ended						9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Jun. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2013 Domestic Tax Authority [Member]	Dec. 31, 2013 State and Local Jurisdiction [Member]	Sep. 30, 2014 Investment One [Member] Maximum [Member] Israel Tax Authority [Member] Ormat Systems Ltd Member	Sep. 30, 2014 Investment One [Member] Israel Tax Authority [Member] Ormat Systems Ltd Member	Sep. 30, 2014 Investment Two [Member] Maximum [Member] Israel Tax Authority [Member] Ormat Systems Ltd Member	Sep. 30, 2014 Investment Two [Member] Israel Tax Authority [Member] Ormat Systems Ltd Member	Dec. 31, 2013 Investment Tax Credit Carryforward [Member] Maximum [Member]	Dec. 31, 2013 Investment Tax Credit Carryforward [Member] Minimum [Member]	Dec. 31, 2013 Investment Tax Credit Carryforward [Member]	Dec. 31, 2013 General Business Tax Credit Carryforward [Member] Maximum [Member]	Dec. 31, 2013 General Business Tax Credit Carryforward [Member] Minimum [Member]	Dec. 31, 2013 General Business Tax Credit Carryforward [Member]	Sep. 30, 2014 Israel Tax Authority [Member] Ormat Systems Ltd Member
Note 11 - Income Taxes (Details) [Line Items]
Effective Income Tax Rate Reconciliation, Percent	26.70%	28.10%		26.50%	34.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%			35.00%
Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount (in Dollars)	$ 895,000	$ 495,000	$ 2,921,000		$ 1,890,000
Operating Loss Carryforwards (in Dollars)							235,400,000	218,100,000
Tax Credit Carryforward Expiration Period															20 years			20 years
Tax Credit Carryforward Expiration Year													2024	2022		2032	2026
Deferred Tax Assets, Investments (in Dollars)						700,000
Deferred Tax Assets, Tax Credit Carryforwards, General Business (in Dollars)						$ 71,300,000
Period For Tax Exemption										2 years		2 years
Effective Income Tax Rate									25.00%		25.00%
Income Tax Incentive Period										5 years		5 years
Effective Income Tax Rate Year One and Year Two																			15.00%
Effective Income Tax Rate Year Three and Year Four																			12.50%
Effective Income Tax Rate Year Five and Thereafter																			16.00%