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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Commitments and contingencies - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) customer	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2024 USD ($)
Titanium Dioxide Pigments
Commitment And Contingencies [Line Items]
TiO2 Customers \| customer	3,000
Feedstock
Commitment And Contingencies [Line Items]
Minimum purchase commitments \| $	$ 583			$ 465
Various Raw Materials and Services
Commitment And Contingencies [Line Items]
Minimum purchase commitments \| $	$ 72			$ 38
Net Sales \| Product Concentration Risk \| Titanium Dioxide Pigments
Commitment And Contingencies [Line Items]
Approximate percent sales by volume	90.00%	92.00%	92.00%
Net Sales \| Customer Concentration Risk \| Titanium Dioxide Pigments \| Top ten customers
Commitment And Contingencies [Line Items]
Approximate percent sales by volume	35.00%	33.00%	32.00%
Net Sales \| Customer Concentration Risk \| Titanium Dioxide Pigments \| One customer
Commitment And Contingencies [Line Items]
Approximate percent sales by volume	12.00%	10.00%	10.00%
TiO2 Customers \| customer	1