Derivative financial instruments, Breakdown of fair value amounts (Details) - Interest Rate Derivatives [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Euros [Member]
Breakdown of fair value amount of derivative financial instruments [Abstract]
Percent of notional amount of debt hedged in next 12 months	100.00%
Percentage of notional amount of debt hedged in year two	75.00%
Cash Flow Hedge [Member]
Breakdown of fair value amount of derivative financial instruments [Abstract]
Assets	$ 11,571	$ 8,230
Liabilities	$ 279,152	$ 329,731

The percentage of the notional amount of the entity's debt hedged with interest rate swaps and options for next twelve months.

No definition available.

+ Details

Name:	aby_PercentageOfNotionalAmountOfDebtHedgedInNextTwelveMonths
Namespace Prefix:	aby_
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Period Type:	duration

- Definition

The percentage of the notional amount of the entity's debt hedged with interest rate swaps and options for year two.

+ References

No definition available.

+ Details

Name:	aby_PercentageOfNotionalAmountOfDebtHedgedInYearTwo
Namespace Prefix:	aby_
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Balance Type:	na
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- References

No definition available.

+ Details

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Namespace Prefix:	ifrs-full_
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- Definition

The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 24A
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_24A_a&doctype=Standard
-URIDate 2018-03-16

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [member]]

+ References

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

Name:	srt_CurrencyAxis=currency_EUR
Namespace Prefix:
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- Details

Name:	ifrs-full_TypesOfHedgesAxis=ifrs-full_CashFlowHedgesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: