EARNINGS PER SHARE (Schedule of Earnings per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Earnings per Share [abstract]
Net income for the period attributable to Fortuna shareholders	$ 57,877	$ 21,553
Add: finance costs on convertible debt, net of $nil tax	$ 3,779
Weighted average number of shares ('000's)	237,998	174,993
Earnings per share - basic	$ 0.24	$ 0.12
Diluted net income for the period	$ 61,656	$ 21,553
Incremental shares from dilutive potential shares	11,445	11,080
Weighted average diluted number of shares (000's)	249,443	186,073
Earnings per share - diluted	$ 0.23	$ 0.12
Convertible debt, net of tax	$ 0

Amount of diluted net income for the period.

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Adjustment to profit (loss) related to finance cost on convertible debt.

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Amount of tax portion of dilutive finance cost on convertible debt.

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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]]

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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).

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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]]

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The number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options.

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

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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.

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