Shareholder remuneration system and earnings per share - Schedule of basic earnings per share (Details) - EUR (€) € / shares in Units, € in Millions	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Basic earnings per share [abstract]
Profit attributable to the Parent (EUR million)	€ 8,973	€ 6,833
Remuneration of contingently convertible preferred securities (CCPS) (EUR million)	(318)	(310)
Net profit for the year	8,655	6,523
Profit or Loss from discontinued operations (non controlling interest net) (EUR million)	1,895	454
Profit or Loss from continuing operations (CCPS net) (EUR million)	€ 6,760	€ 6,069
Weighted average number of shares outstanding (in shares)	14,458,003,078	14,995,834,683
Basic earnings per share (in euro per share)	€ 0.60	€ 0.43
Basic earnings per share from discontinued operations (in euro per share)	0.13	0.03
Basic earnings per share from continuing operations (in euro per share)	€ 0.47	€ 0.40

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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Basic earnings (loss) per share from continuing operations. [Refer: Basic earnings (loss) per share; Continuing operations, unless line item indicates otherwise [member]]

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Basic earnings (loss) per share from discontinued operations. [Refer: Basic earnings (loss) per share; Discontinued operations [member]]

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The profit (loss) attributable to ordinary equity holders of the parent entity. [Refer: Profit (loss)]

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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 profit (loss) from continuing operations attributable to ordinary equity holders of the parent entity, adjusted for the effects of all dilutive potential ordinary shares. [Refer: Profit (loss) from continuing operations]

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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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Adjustment To Profit (Loss) For Remuneration Of Contingently Convertible Preferred Securities

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