EMPLOYEE BENEFITS - Sensitivity analysis (Details) - COP ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Actuarial assumption of discount rates [member] \| Post-Employment benefits
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Decrease	$ 10,207	$ 12,270
Increase	(9,676)	(11,583)
Actuarial assumption of discount rates [member] \| Long-Term Benefits
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Decrease	3,683	3,815
Increase	(3,534)	(3,642)
Actuarial assumption of expected rates of salary increases [member] \| Post-Employment benefits
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Decrease	(1,323)	(2,568)
Increase	1,383	2,693
Actuarial assumption of expected rates of salary increases [member] \| Long-Term Benefits
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Decrease	(4,497)	(4,483)
Increase	4,661	4,759
Actuarial assumption of expected rates of pension increases [member] \| Post-Employment benefits
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Decrease	(12,903)	(11,323)
Increase	$ 8,082	$ 11,923

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 increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [domain]]

+ References

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

The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [domain]]

+ References

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