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.

No definition available.

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- Definition

The amount of the estimated financial effect of contingent liabilities. [Refer: Contingent liabilities [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of liabilities of uncertain timing or amount, including provisions for employee benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Legal Proceedings Provision, Probable Loss Risk

+ References

No definition available.

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Provisions - Tax-related litigation (Details) - EUR (€) € in Millions	Jun. 30, 2022	Dec. 31, 2021
Disclosure of other provisions [line items]
Provisions	€ 8,590	€ 9,583
Banco Santander (Brazil)
Disclosure of other provisions [line items]
Tax legal obligations with probable loss risk	1,024
Estimated financial effect of contingent liabilities	4,530
Legal case relating to questionable deduction of loan losses in income tax returns \| Banco Santander (Brazil)
Disclosure of other provisions [line items]
Provisions	0
Legal case relating to tax deductibility of sale of shares \| Banco Santander (Brazil)
Disclosure of other provisions [line items]
Provisions	0
Legal case appeal relating to deduction of expenses in income tax (IRPJ and CSLL) \| Banco Santander (Brazil)
Disclosure of other provisions [line items]
Provisions	0
Legal case relating to tax deductibility of amortization of goodwill arising on acquisition \| Banco Santander (Brazil) \| Banco Comercial e de Investimento Sudameris S.A
Disclosure of other provisions [line items]
Provisions	0
Legal case relating to tax deductibility of amortization of goodwill arising on acquisition \| Banco Santander (Brazil) \| Getnet Tecnologia Proces S.A.
Disclosure of other provisions [line items]
Provisions	0
Legal case related to infringement notices initiated by tax authorities regarding offsetting tax losses \| Banco Santander (Brazil)
Disclosure of other provisions [line items]
Provisions	€ 0