Project debt, Repayment schedule (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Repayment schedule [Abstract]
Project debt	$ 5,200,217	$ 5,237,614
Remainder of 2021 [Member]
Repayment schedule [Abstract]
Interest repayment	59,661
Nominal repayment	265,551
Between January and March 2022 [Member]
Repayment schedule [Abstract]
Project debt	23,216
Between April and December 2022 [Member]
Repayment schedule [Abstract]
Project debt	297,361
2021 [Member]
Repayment schedule [Abstract]
Interest repayment		19,287
Nominal repayment		293,059
2022 [Member]
Repayment schedule [Abstract]
Project debt		328,364
2023 [Member]
Repayment schedule [Abstract]
Project debt	348,614	355,806
2024 [Member]
Repayment schedule [Abstract]
Project debt	363,872	371,548
2025 [Member]
Repayment schedule [Abstract]
Project debt	497,298	508,843
Subsequent Years [Member]
Repayment schedule [Abstract]
Project debt	$ 3,344,644	$ 3,360,707

The current and non-current portions of project debt issued at the project level under project finance.

No definition available.

Name:	aby_LongTermAndShortTermProjectDebt
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of current interest payable. [Refer: Interest payable]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2020-01-01

+ Details

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

- References

No definition available.

+ Details

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

- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

+ Details

Name:	ifrs-full_NotionalAmount
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	ifrs-full_MaturityAxis=aby_LaterThanThreeMonthsAndNotLaterThanOneYearOfCurrentYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_LaterThanOneMonthAndNotLaterThanThreeMonthsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_LaterThanThreeMonthsAndNotLaterThanOneYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_NotLaterThanOneYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_LaterThanOneYearAndNotLaterThanTwoYearsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_LaterThanTwoYearsAndNotLaterThanThreeYearsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_LaterThanThreeYearsAndNotLaterThanFourYearsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_LaterThanFourYearsAndNotLaterThanFiveYearsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_LaterThanFiveYearsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: