Earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings per share [Abstract]
Potential issuance of shares on settlement of Green Exchangeable Notes (in shares)	3,347,305
Profit from continuing operations attributable to Atlantica	$ 11,968	$ 62,135	$ 41,596
Average number of ordinary shares outstanding - basic (in shares)	101,879,000	101,063,000	100,217,000
Average number of ordinary shares outstanding - diluted (in shares)	103,392,000	101,063,000	100,217,000
Earnings per share from continuing operations - basic and diluted (in dollars per share)	$ 0.12	$ 0.61	$ 0.42
Earnings per share from profit for the period - basic and diluted (in dollars per share)	$ 0.12	$ 0.61	$ 0.42

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2020-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2020-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_AdjustedWeightedAverageShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of earnings per share when the basic and diluted measurements are equal. [Refer: Basic earnings (loss) per share; Diluted earnings (loss) per share]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 85
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_85&doctype=Standard
-URIDate 2020-01-01

+ Details

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

- Definition

Basic and diluted earnings (loss) per share from continuing operations. [Refer: Basic and diluted earnings (loss) per share]

+ References

+ Details

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

- Definition

The number of dilutive potential ordinary shares that relate to the assumed conversion of the entity's convertible instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 33
-IssueDate 2020-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2020-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_DilutiveEffectOfConvertibleInstrumentsOnNumberOfOrdinaryShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

The profit (loss) from continuing operations attributable to ordinary equity holders of the parent entity. [Refer: Continuing operations [member]; Profit (loss) from continuing operations]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2020-01-01
-Paragraph 70
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2020-en-r&anchor=para_70_a&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_ProfitLossFromContinuingOperationsAttributableToOrdinaryEquityHoldersOfParentEntity
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

+ References

+ Details

Name:	ifrs-full_WeightedAverageShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration