Equity - Other comprehensive income, items not reclassified to profit or loss - Actuarial gains or losses on defined benefit benefit pension plans (Details) - EUR (€) € in Millions	6 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Items not reclassified to profit or loss
Decrease in actuarial losses	€ 843
Pension defined benefit plans \| UK
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	€ 386
Discount rates	3.84%	1.90%
Pension defined benefit plans \| Spain
Items not reclassified to profit or loss
Discount rates	3.10%	0.90%
Pension defined benefit plans \| Germany
Items not reclassified to profit or loss
Discount rates	3.55%	1.45%
Pension defined benefit plans \| Portugal
Items not reclassified to profit or loss
Discount rates	2.60%	1.10%
Pension defined benefit plans \| Brazil
Items not reclassified to profit or loss
Discount rates	9.12%	8.39%
Discount rate actuarial assumptions \| Other regions
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	€ (89)
Discount rate actuarial assumptions \| Pension defined benefit plans \| Spain
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	229
Discount rate actuarial assumptions \| Pension defined benefit plans \| Germany
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	161
Discount rate actuarial assumptions \| Pension defined benefit plans \| Portugal
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	110
Discount rate actuarial assumptions \| Pension defined benefit plans \| Brazil
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	€ 46

The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2021-01-01
-Paragraph 144
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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 141
-Subparagraph c
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_c_iii&doctype=Standard
-URIDate 2021-03-24

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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No definition available.

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_c&doctype=Standard
-URIDate 2021-03-24

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