Amount investment in the project company which is the owner of a concessional asset.

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The current and non-current portions of credit facilities with financial entities, notes and bonds received at the corporate parent level.

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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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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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The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Financial liabilities; Derivatives [member]]

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Financial instruments by category, Reconciliation to statement of financial position (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financial Assets [Abstract]
Derivative assets	$ 8,230	$ 3,822
Investment in Ten West Link	2,088
Abengoa debt and Equity instruments	1,715
Preferred equity in ACBH		30,488
Other financial investments	243,347	263,501
Clients and other receivables	244,449	207,621
Cash and cash equivalents	669,387	594,811	$ 514,712	$ 354,154
Total financial assets	1,169,216	1,100,243
Financial Liabilities [Abstract]
Corporate debt	643,083	668,201
Project debt	5,475,208	5,330,467	$ 5,470,669
Related parties - non-current	141,031	101,750
Trade and other current liabilities	155,144	160,505
Derivative liabilities	329,731	349,266
Total financial liabilities	6,744,197	6,610,189
Hedging Derivatives [Member]
Financial Liabilities [Abstract]
Corporate debt	0	0
Project debt	0	0
Related parties - non-current	0	0
Trade and other current liabilities	0	0
Derivative liabilities	329,731	349,266
Total financial liabilities	329,731	349,266
Hedging Derivatives [Member]
Financial Assets [Abstract]
Derivative assets	8,230	3,822
Investment in Ten West Link	0
Abengoa debt and Equity instruments	0
Preferred equity in ACBH		0
Other financial investments	0	0
Clients and other receivables	0	0
Cash and cash equivalents	0	0
Total financial assets	8,230	3,822
Payables [Member]
Financial Liabilities [Abstract]
Corporate debt	643,083	668,201
Project debt	5,475,208	5,330,467
Related parties - non-current	141,031	101,750
Trade and other current liabilities	155,144	160,505
Derivative liabilities	0	0
Total financial liabilities	6,414,466	6,260,923
Loans and Receivables [Member]
Financial Assets [Abstract]
Derivative assets	0	0
Investment in Ten West Link	2,088
Abengoa debt and Equity instruments	0
Preferred equity in ACBH		0
Other financial investments	243,347	263,501
Clients and other receivables	244,449	207,621
Cash and cash equivalents	669,387	594,811
Total financial assets	1,159,271	1,065,933
Available for Sale Financial Assets [Member]
Financial Assets [Abstract]
Derivative assets	0	0
Investment in Ten West Link	0
Abengoa debt and Equity instruments	1,715
Preferred equity in ACBH		30,488
Other financial investments	0	0
Clients and other receivables	0	0
Cash and cash equivalents	0	0
Total financial assets	$ 1,715	$ 30,488