Name:	san_CommonEquityTierTwoCapitalRatio
Namespace Prefix:	san_
Data Type:	dtr-types1: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:	dtr-types1: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:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action. Also known as "ordinary eligible capital."

No definition available.

Name:	san_IfrsCommonEquityTierOneCapitalRequiredForCapitalAdequacy
Namespace Prefix:	san_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of risk-weighted assets as calculated in accordance with international regulatory capital standards.

No definition available.

Name:	san_IfrsRiskWeightedAssets
Namespace Prefix:	san_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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

No definition available.

Name:	san_IfrsTierOneRiskBasedCapitalToRiskWeightedAssets
Namespace Prefix:	san_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

Tier 2 risk-based capital as defined in the international regulations.

No definition available.

Name:	san_IfrsTierTwoRiskBasedCapital
Namespace Prefix:	san_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

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

The amount by which the company's Common Equity Tier One Capital exceeds the minimum required for capital adequacy purposes. Also known as "additional eligible capital."

No definition available.

Name:	san_TierOneCapitalInExcessOfCommonEquityTierOneCapital
Namespace Prefix:	san_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount of Tier 1 capital beyond that included in Common Equity Tier 1 capital divided by risk-weighted assets, which are assets that are weighted for credit risk.

No definition available.