The annual interest rate on corporate tradable bonds.

No definition available.

Name:	aby_CorporateTradableBondsInterestRate
Namespace Prefix:	aby_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The interest percentage of corporate tradable bonds which is paid in cash.

+ References

No definition available.

+ Details

Name:	aby_CorporateTradableBondsInterestRatePaidInCash
Namespace Prefix:	aby_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The interest percentage of corporate tradable bonds which is paid in kind.

+ References

No definition available.

+ Details

Name:	aby_CorporateTradableBondsInterestRatePaidInKind
Namespace Prefix:	aby_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to period for which the corporate tradable bonds are extendable subject further to the senior old money creditors consent in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	aby_CorporateTradableBondsIssuedExtendablePeriod
Namespace Prefix:	aby_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to the period for which corporate tradable bonds issued are subject to stay in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	aby_CorporateTradableBondsIssuedPeriod
Namespace Prefix:	aby_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	aby_DividendsRetained
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of gain (loss) resulting from sale of major part of debt and equity instruments.

+ References

No definition available.

+ Details

Name:	aby_GainLossFromSaleOfDebtAndEquityInstruments
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total span, length or measured distance of transmission lines.

+ References

No definition available.

+ Details

Name:	aby_LengthOfTransmissionLines
Namespace Prefix:	aby_
Data Type:	num:lengthItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of loss (gain) from derecognition of the fair value assigned to the ACBH preferred equity investment and recognition of the Abengoa Debt and Equity Instruments.

+ References

No definition available.

+ Details

Name:	aby_LossGainFromDerecognitionOfFairValueAssignedToPreferredEquityInvestmentAndRecognitionOfDebtAndEquityInstruments
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from sale of tradable notes.

+ References

No definition available.

+ Details

Name:	aby_ProceedsFromSaleOfTradableNotes
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	aby_RestructuringAgreementAbstract
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Period Type:	duration

- Definition

The amount of cash which has been contributed in exchange of tradable notes under restructuring agreement.

+ References

No definition available.

+ Details

Name:	aby_RestructuringAgreementCashContributionInExchangeOfTradableNotes
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The fair value of the tradable notes received by the entity under the restructuring agreement.

+ References

No definition available.

+ Details

Name:	aby_RestructuringAgreementFairValueOfTradableNotes
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage of voting equity interests acquired in a business combination. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2016-01-13
-Paragraph B64
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2016-03-30&anchor=para_B64_c&doctype=Appendix&seq=2
-URIDate 2016-03-31

+ Details

Name:	ifrs-full_PercentageOfVotingEquityInterestsAcquired
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	ifrs-full_BorrowingsByNameAxis=aby_NewMoney1TradableNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfFinancialAssetsAxis=aby_TenWestLinkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=aby_AbengoaSAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Financial instruments by category, Restructuring agreement of Abengoa (Details) $ in Millions					1 Months Ended	12 Months Ended
	Mar. 31, 2017 USD ($)	Mar. 15, 2017 USD ($)	Feb. 28, 2017 mi	Feb. 24, 2017 USD ($)	Apr. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) mi	Dec. 31, 2014
Restructuring agreement of Abengoa [Abstract]
Dividends retained from Abengoa				$ 10.4
Percentage interest acquired			12.50%
Length of transmission lines \| mi			114
New Money Tradable Notes [Member]
Restructuring agreement of Abengoa [Abstract]
Restructuring agreement assigned tradable notes amount	$ 44.5
Restructuring agreement cash contribution in exchange of tradable notes	$ 43.6
Ten West Link [Member]
Restructuring agreement of Abengoa [Abstract]
Percentage interest acquired						12.50%
Length of transmission lines \| mi						114
Abengoa [Member]
Restructuring agreement of Abengoa [Abstract]
Corporate tradable bonds issued period						5 years 6 months
Corporate tradable bonds issued extendable period						2 years
Corporate tradable bonds interest rate	1.50%
Corporate tradable bonds interest rate paid in cash	0.25%
Corporate tradable bonds interest rate paid in kind	1.25%
Loss from derecognition of fair value assigned to preferred equity investment and recognition of debt and equity instruments						$ 5.8
Profit resulting from sale of major part of debt and equity instruments						$ 6.5
Dividends retained from Abengoa		$ 10.4
Percentage interest acquired							64.28%
Abengoa [Member] \| New Money Tradable Notes [Member]
Restructuring agreement of Abengoa [Abstract]
Proceeds from sale of tradable notes					$ 44.9