Earnings Per Share - Summary of Earnings Per Share (Detail) - AUD ($)	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Earnings per share [line items]
Loss after income tax attributable to the owners of Immutep Limited	$ (61,434,165)	$ (42,716,625)	$ (39,896,348)
Weighted average number of ordinary shares used in calculating basic earnings per share (EPS)	1,455,818,442	1,201,061,930	892,399,810
Weighted average number of ordinary shares used in calculating diluted earnings per share (EPS)	1,455,818,442	1,201,061,930	892,399,810
Basic earnings per share	$ (0.0422)	$ (0.0356)	$ (0.0447)
Diluted earnings per share	$ (0.0422)	$ (0.0356)	$ (0.0447)

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 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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