Earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Earnings per share [Abstract]
Potential issuance of shares on settlement of Green Exchangeable Notes (in shares)	3,347,305	3,347,305
Potential issuance of subsribed shares (in shares)		510,169
Profit/(loss) attributable to Atlantica	$ (18,166)	$ 61,209
Average number of ordinary shares outstanding - basic (in shares)	110,749,000	101,602,000
Average number of ordinary shares outstanding - diluted (in shares)	114,156,000	102,499,000
Earnings per share for the period - basic (in dollars per share)	$ (0.16)	$ 0.60
Earnings per share for the period - diluted (in dollars per share)	$ (0.16)	$ 0.60

The number of dilutive potential ordinary shares that relate to the contingently issuable shares of the entity.

No definition available.

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- Definition

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]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

+ References

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- 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
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- References

No definition available.

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- Definition

The profit (loss) from continuing and discontinued operations attributable to owners of the parent. [Refer: Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- 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

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