FAIR VALUE MEASUREMENTS - Additional disclosures of the Plan investments whose fair value is estimated using net asset value per share (Details) - ECOLAB SAVINGS PLAN AND ESOP - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
FAIR VALUE MEASUREMENTS
Investment at fair value	$ 4,467,957	$ 4,014,153
Common/collective trusts
FAIR VALUE MEASUREMENTS
Investment at fair value	3,426,024	1,819,183
Common/collective trusts \| Net asset value per share
FAIR VALUE MEASUREMENTS
Investment at fair value	$ 3,426,024	$ 1,819,183

Fair value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract not meeting fully-benefit responsive investment criteria.

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+ Details

- Definition

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.

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