Earnings per share (Details) - EUR (€) € / shares in Units, € in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings per share
Weighted average number of shares used for basic earnings per share	3,592,249,603	3,601,140,133	3,601,140,133
Potential shares to be issued for ILT incentive plan	2,251,406	2,782,584	1,691,413
Weighted average number of shares used for diluted earnings per share	3,594,501,009	3,603,922,717	3,602,831,546
Eni's net profit	€ 148	€ 4,126	€ 3,374
Basic earnings per share	€ 0.04	€ 1.15	€ 0.94
Diluted earnings per share	€ 0.04	€ 1.15	€ 0.94

Disclosure Of Earnings Per Share Explanatory.

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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]]

+ References

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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) attributable to ordinary equity holders of the parent entity. [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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