Name:	san_CommonEquityCapitalConservationBufferPercentage
Namespace Prefix:	san_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Percentage of Common Equity Pillar One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

No definition available.

Name:	san_CommonEquityPillarOneCapitalRatio
Namespace Prefix:	san_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Percentage of Common Equity Pillar 2 Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

No definition available.

Name:	san_CommonEquityPillarTwoCapitalRatio
Namespace Prefix:	san_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Percentage of countercyclical buffer on common equity Tier1 capital.

No definition available.

Name:	san_CommonEquityTier1CapitalCountercyclicalBufferPercentage
Namespace Prefix:	san_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Additional percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets required for an entity defined as a systemically important financial institution (SIFI), as defined by regulatory framework.

No definition available.

Name:	san_CommonEquityTierOneCapitalRatioGlobalSystemicallyImportantEntity
Namespace Prefix:	san_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Total Capital divided by risk weighted assets as defined in the international regulations.

No definition available.

Name:	san_IfrsCapitalToRiskWeightedAssets
Namespace Prefix:	san_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

No definition available.

Name:	san_IfrsCommonEquityTierOneCapitalRatio
Namespace Prefix:	san_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

No definition available.

Name:	san_IfrsComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems
Namespace Prefix:	san_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Tier 1 capital divided by risk weighted assets as defined by international regulations.

No definition available.