Earnings (Loss) Per Share - Summary Of Loss (Profit) Per Share (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2023 CAD ($) $ / shares shares	Dec. 31, 2023 $ / shares	Dec. 31, 2022 CAD ($) $ / shares shares	Dec. 31, 2022 $ / shares
Basic earnings (loss) per share
Net income (loss) attributable to NexGen shareholders \| $	$ 80,816		$ (56,587)
Weighted average number of common shares	498,243,824		479,680,438
Basic earnings (loss) per share \| (per share)	$ 0.16	$ 0.16	$ (0.12)	$ (0.12)
Diluted earnings (loss) per share
Diluted earnings (loss) available to NexGen shareholders \| $	$ 80,816		$ (56,587)
Weighted average number of common shares	498,243,824		479,680,438
Effect of share options on issue	14,698,606
Weighted average number of common shares (diluted)	529,214,619		479,680,438
Diluted earnings (loss) per share \| (per share)	$ 0.16	$ 0.16	$ (0.12)	$ (0.12)

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 potential dilutive effect on the weighted average number of 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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