Commitments and contingencies - Summary of Approximate Percentage of TiO2 Sales by Volume (Details) - Net Sales - Geographic Concentration Risk	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Europe
Schedule Of Net Sales By Geographical Segment [Line Items]
Approximate percent sales by volume	44.00%	45.00%	46.00%
North America
Schedule Of Net Sales By Geographical Segment [Line Items]
Approximate percent sales by volume	41.00%	39.00%	37.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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