Distribution of the Bank's profit, etc. - EPS Basic (Details) - EUR (€) € / shares in Units, € in Millions	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Basic earnings per share [abstract]
Profit (loss), attributable to owners of parent	€ 3,231	€ 3,752
Remuneration of contingently convertible preference shares (CCP) (millions of euros)	(298)	(266)
Net profit for the year	2,933	3,486
Profit or Loss from continuing operations (net of non-controlling interests and CCP) (millions of euros)	€ 2,933	€ 3,486
Weighted average number of shares outstanding	16,231,374,256	16,129,055,793
Total basic earnings (loss) per share	€ 0.180	€ 0.220
Basic earnings per share from continuing operations (euros)	€ 0.180	€ 0.220

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 [member]]

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The increase (decrease) in equity resulting from the conversion of convertible instruments.

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The profit (loss) attributable to ordinary equity holders of the parent equity. [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 equity, 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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