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Note 1 - General and Basis of Presentation (Details) (USD $)	0 Months Ended	3 Months Ended		12 Months Ended	0 Months Ended	3 Months Ended
	Feb. 15, 2015	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Mar. 26, 2014	Jun. 30, 2014	Feb. 14, 2015	Dec. 31, 2013
Note 1 - General and Basis of Presentation (Details) [Line Items]
Percentage of Public Float Before Transition to Noncontrolled Public Company							40.00%
Percentage of Public Float After Transition to Noncontrolled Public Company	76.00%
Share Exchange Shares Granted Per Share (in Shares)	0.2592ora_ShareExchangeSharesGrantedPerShare
Common Stock, Shares, Issued (in Shares)	3,000,000us-gaap_CommonStockSharesIssued	48,828,331us-gaap_CommonStockSharesIssued		45,537,162us-gaap_CommonStockSharesIssued
Common Stock, Shares, Outstanding (in Shares)	48,500,000us-gaap_CommonStockSharesOutstanding	48,828,331us-gaap_CommonStockSharesOutstanding		45,537,162us-gaap_CommonStockSharesOutstanding			45,500,000us-gaap_CommonStockSharesOutstanding
Sale of Stock, Consideration Received on Transaction	$ 15,400,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		7,000	36,000
Interest Expense		17,828,000us-gaap_InterestExpense	20,518,000us-gaap_InterestExpense
Income Tax Expense (Benefit)		5,459,000us-gaap_IncomeTaxExpenseBenefit	6,320,000us-gaap_IncomeTaxExpenseBenefit
Cash, Cash Equivalents, and Short-term Investments		70,724,000	47,927,000	40,230,000				57,354,000
Accounts Receivable, Net, Current		56,300,000us-gaap_AccountsReceivableNetCurrent		48,609,000us-gaap_AccountsReceivableNetCurrent
Provision for Doubtful Accounts		0us-gaap_ProvisionForDoubtfulAccounts
Primary Customers [Member] \| Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Concentration Risk, Percentage		47.00%		69.00%
Sierra Pacific Power Company And Nevada Power Company [Member] \| Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Concentration Risk, Percentage		24.00%	15.30%
Southern California Edison Company [Member] \| Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Concentration Risk, Percentage		8.80%	12.10%
Kenya Power And Lighting Co Limited [Member] \| Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Concentration Risk, Percentage		17.80%	14.30%
Heber Solar Project [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Sales Price of Disposition					35,250,000
Proceeds from Sales of Business, Affiliate and Productive Assets			15,000,000			20,250,000
Gain (Loss) on Sale of Project						7,600,000
Reclassification out of Accumulated Other Comprehensive Income [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Interest Expense		12,000	58,000
Income Tax Expense (Benefit)		5,000	22,000
UNITED STATES
Note 1 - General and Basis of Presentation (Details) [Line Items]
Cash, Cash Equivalents, and Short-term Investments		41,175,000		23,488,000
Foreign Countries [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Cash, Cash Equivalents, and Short-term Investments		41,190,000		24,304,000
Accounts Receivable, Net, Current		26,790,000		21,935,000
Maximum [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Cash, FDIC Insured Amount								250,000
Aggregate Shares Issued [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Conversion of Stock, Shares Issued (in Shares)	30,200,000
Shares Issued to Self, Deducted [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Conversion of Stock, Shares Issued (in Shares)	27,200,000
Sale of Stock, Other Assets Received [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Sale of Stock, Consideration Received Per Transaction	600,000
Sale of Stock, Land and Buildings Received [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Sale of Stock, Consideration Received Per Transaction	12,100,000
Sale of Stock, Liabilities Assumed [Member]
Note 1 - General and Basis of Presentation (Details) [Line Items]
Sale of Stock, Consideration Received Per Transaction	$ 500,000