Note 12 - Tax Monetization Transaction (Details) (USD $)	9 Months Ended		1 Months Ended							0 Months Ended	1 Months Ended			3 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Jan. 24, 2013 Common Class A [Member] Ormat Nevada Ortp LLC [Member]	Jan. 24, 2013 Common Class B [Member] Ormat Nevada Ortp LLC [Member]	Dec. 31, 2011 Capital Unit, Class A [Member] Ormat Nevada Ortp LLC [Member]	Feb. 03, 2011 Capital Unit, Class A [Member] Ormat Nevada Ortp LLC [Member]	Dec. 31, 2011 Capital Unit, Class B [Member] Ormat Nevada Ortp LLC [Member]	Feb. 03, 2011 Capital Unit, Class B [Member] Ormat Nevada Ortp LLC [Member]	Dec. 31, 2010 Capital Unit, Class B [Member] Ormat Nevada Ortp LLC [Member]	Feb. 03, 2011 Ormat Nevada Ortp LLC [Member]	Jan. 24, 2013 Ormat Nevada Ortp LLC [Member]	Oct. 30, 2009 Ormat Nevada Ortp LLC [Member]	Jun. 30, 2007 Ormat Nevada Ortp LLC [Member]	Mar. 31, 2014 Ormat Nevada Ortp LLC [Member]	Dec. 31, 2009 Ormat Nevada Ortp LLC [Member]	Dec. 31, 2008 Ormat Nevada Ortp LLC [Member]	Dec. 31, 2007 Ormat Nevada Ortp LLC [Member]	Dec. 31, 2010 Ormat Nevada Ortp LLC [Member]
Note 12 - Tax Monetization Transaction (Details) [Line Items]
Number Of Facilities													4
Proceeds From Sale Of Equity Units (in Dollars)																$ 63,000,000	$ 71,800,000
Percentage Of Ownership Interests Flip Date																		95.00%
Percentage Of Ownership Interests By Noncontrolling Owners Flip Date										5.00%		3.50%						5.00%
Percentage Of Ownership Interests					75.00%	75.00%	25.00%	7.50%										82.50%
Ownership Percentage Of Common Shares Outstanding								30.00%
Ownership Percentage Of Common Shares Outstanding By NonControlling Interest									70.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners									17.50%
Payments for Repurchase of Redeemable Noncontrolling Interest (in Dollars)												18,500,000
Gain From Repurchase Of Interests At Discount (in Dollars)															13,300,000
Adjustments To Additional Paid In Capital Purchase Of Noncontrolling Interest (in Dollars)															1,100,000
Percentage Of Ownership Interests Purchased From Noncontrolling Owners										1.50%					1.50%
Proceeds Sale Minority Interest (in Dollars)										24,900,000
Noncontrolling Interest, Increase from Subsidiary Equity Issuance (in Dollars)	257,000	5,151,000								2,300,000
Proceeds from Sales of Business, Affiliate and Productive Assets (in Dollars)											35,700,000
Additional Proceeds as Percentage of Production Tax Credit											25.00%
Final Additional Payments Expected Date											Dec. 31, 2016
Expected Future Payments (in Dollars)											11,000,000
Proceeds from Noncontrolling Interests (in Dollars)	$ 2,234,000													$ 2,200,000
Percentage of Distributable Cash After Flip Date											97.50%
Percentage of Taxable Income After Flip Date											95.00%
Percentage Allocation Of Income and Loss											5.00%
Percentage Allocation of Cash											2.50%
Common Stock Voting Rights Percentage			75.00%	25.00%