v3.8.0.1

Other information (Details) - USD ($) $ / shares in Units, $ in Millions	Feb. 28, 2018	Dec. 31, 2017
Restricted net assets [Abstract]
Restricted net assets		$ 566
Subsequent Event [Member]
Subsequent Events [Abstract]
Dividends declared (in dollars per share)	$ 0.31

X

- Definition

The amount of the registrant's share of subsidiaries' net assets (assets less the sum of liabilities, redeemable preferred stock, and noncontrolling interests) that may not be transferred to the parent in the form of loans, dividends, etc., without a third party's consent.

+ References

No definition available.

+ Details

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

X

- References

No definition available.

+ Details

Name:	aby_RestrictedNetAssetsAbstract
Namespace Prefix:	aby_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount, per share, of dividends proposed or declared before financial statements were authorised for issue but not recognised as distribution to owners.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2016-01-13
-Paragraph 137
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2016-03-30&anchor=para_137_a&doctype=Standard
-URIDate 2016-03-31

+ Details

Name:	ifrs-full_DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwnersPerShare
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	ifrs-full_NonadjustingEventsAfterReportingPeriodAxis=aby_AnnouncementOfDeclaredDividendsApprovedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: