v3.8.0.1

Related parties (Details) $ in Thousands, € in Millions			3 Months Ended	12 Months Ended
	Nov. 30, 2017 USD ($)	Feb. 24, 2017 USD ($)	Sep. 30, 2017 EUR (€)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Details of Balances [Abstract]
Current receivables with related parties				$ 11,567	$ 12,031
Non-current receivables with related parties				2,108	30,505
Current payables with related parties				63,409	61,338
Non-current payables with related parties				141,031	101,750
Receivables from related parties				1,715
Preferred equity in ACBH					30,488
Transactions With Related Party [Abstract]
Financial income				1,007	3,298	$ 3,464
Financial expenses				(463,717)	(408,007)	(333,921)
Dividends retained from Abengoa		$ 10,400
Related Parties [Member]
Details of Balances [Abstract]
Receivables from related parties				1,715
Preferred equity in ACBH					30,488
Transactions With Related Party [Abstract]
Dividends retained from Abengoa				10,400	28,000
Income for cancellation of subordinated debt					7,600
Income for discounts received for prepayment of payables					1,700
Subsidiaries [Member]
Transactions With Related Party [Abstract]
Sales				0	0	44,260
Services rendered				3,495	1,220	523
Services received				(114,416)	(115,779)	(106,737)
Financial income				74	60	1,466
Financial expenses				$ (1,154)	$ (2,460)	$ (1,968)
Abengoa [Member]
Transactions With Related Party [Abstract]
Term to maintain guarantees and letters of credit				5 years
Guarantees amount				$ 31,500
Other existing debts receivables | €			€ 7.8
Guarantees amount replaced				$ 112,000
Abengoa [Member] | Solana [Member]
Transactions With Related Party [Abstract]
Performance consideration receivable	$ 120,000
Performance obligations proceeds applied to project debt	80,000
Performance obligations proceeds applied to additional plant repairs	25,000
Other obligations	15,000
Other obligations per semester	6,500
Recognition period of other contingnt obligations considered				10 years
Performance obligations proceeds received from Abengoa	$ 42,500
Abengoa [Member] | Solana and Mojave [Member]
Transactions With Related Party [Abstract]
Minimum ownership requirement percentage	16.00%

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Dividends retained from Abengoa related to the preferred equity investment in Abengoa Concessoes Brasil Holding (ACBH), which is a subsidiary of Abengoa engaged in the development, construction, investment and management of contracted concessions in Brazil, comprised mostly of transmission lines. Retention is based on the underlying investment agreement supported by the additional agreement reached with Abengoa in the third quarter of 2016.

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The amount of finance income related to the cancellation of subordinated debt Solnova Electricidad S.A. owed to Abener, a subsidiary of Abengoa.

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The amount of finance income for discounts received from Abengoa for the prepayment of payables.

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Refers to guarantees issued by a related party on behalf of or for the benefit of the entity.

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The minimum percentage of ownership in a concessional asset required that will trigger a change of ownership clause for project financing arrangements.

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Refers to other existing debts receivables from a related party.

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The amount of contingent liabilities recognized that the entity does not separately disclose in the same statement or note.

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The amount of consideration to be received by Solana as a performance compensation conditioned by a signed consent with DOE.

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The amount of performance obligations proceeds used for additional repairs of plant.

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The estimated amount of project debt to be prepaid from performance obligations proceeds.

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The performance obligations proceeds received resulting from related party transactions.

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An exchangeable preferred equity investment in ACBH, a subsidiary holding company of Abengoa, that is engaged in the development, construction, investment and management of contracted concessions in Brazil, consisting mostly of electric transmission lines.

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The recognition period of other contingent obligations considered.

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Instruments of debt and equity of Abengoa received pursuant the the agreement reached with Abengoa with respect to the ACBH preferred equity instrument.

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Refers to the replacement amount of guarantees previously issued by Abengoa related to operations of technical nature.

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Period of time Abengoa agreed to maintain any guarantees and letters of credit under a revolving credit line in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of costs associated with financing activities of the entity.

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The amount of non-current payables due to related parties. [Refer: Related parties [member]; Payables to related parties]

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The amount of revenue arising from the rendering of services in related party transactions. [Refer: Revenue; Related parties [member]]

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The amount of revenue arising from the sale of goods in related party transactions. [Refer: Revenue; Related parties [member]]

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The amount of services received in related party transactions. [Refer: Related parties [member]]

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The amount of current receivables due from related parties. [Refer: Related parties [member]]

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