RISK MANAGEMENT - Structural foreign exchange risk - General information (Details)	12 Months Ended
Dec. 31, 2025
Disclosure of risk management [abstract]
Percentage of Average Difference in Foreign Currency Denominated Rights and Foreign Currency Denominated Obligations on Unconsolidated Basis	20.00%
Percentage of Average Difference in Foreign Currency Denominated Rights and Foreign Currency Denominated Obligations on Consolidated Basis	40.00%

The percentage of average difference in foreign currency denominated rights and foreign currency denominated obligations including both on and off balance sheet positions on unconsolidated basis.

No definition available.

Name:	aval_PercentageOfAverageDifferenceInForeignCurrencyDenominatedRightsAndForeignCurrencyDenominatedObligationsOnUnconsolidatedBasis
Namespace Prefix:	aval_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration