Business segment information - Segment Operating Performance (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Business segment information | ||||
| Net sales | $ 606.1 | $ 540.4 | $ 1,166.2 | $ 1,079.0 |
| Cost of sales | 486.0 | 462.3 | 943.1 | 878.4 |
| Gross margin | 120.1 | 78.1 | 223.1 | 200.6 |
| Operating income | 67.7 | 35.5 | 100.6 | 85.6 |
| Interest income and other | 4.0 | 3.7 | 7.5 | 8.0 |
| Other components of net periodic pension and OPEB expense | (0.8) | (0.7) | (1.6) | (1.5) |
| Changes in market value of Valhi common stock held by subsidiaries | 0.1 | 0.6 | (1.7) | |
| General expenses, net | (9.0) | (9.2) | (16.3) | (17.1) |
| Interest expense | (14.7) | (13.8) | (29.4) | (27.0) |
| Income before income taxes | 47.3 | 15.5 | 61.4 | 46.3 |
| Chemicals | ||||
| Business segment information | ||||
| Net sales | 558.1 | 494.4 | 1,067.9 | 984.2 |
| Cost of sales | 455.8 | 432.1 | 882.8 | 815.5 |
| Gross margin | 102.3 | 62.3 | 185.1 | 168.7 |
| Operating income | 40.4 | 10.3 | 54.9 | 51.5 |
| Component products | ||||
| Business segment information | ||||
| Net sales | 43.6 | 40.3 | 84.2 | 80.6 |
| Cost of sales | 28.1 | 27.4 | 55.4 | 55.5 |
| Gross margin | 15.5 | 12.9 | 28.8 | 25.1 |
| Operating income | 8.9 | 6.3 | 16.0 | 12.2 |
| Real estate management and development | ||||
| Business segment information | ||||
| Net sales | 4.4 | 5.7 | 14.1 | 14.2 |
| Cost of sales | 2.1 | 2.8 | 4.9 | 7.4 |
| Gross margin | 2.3 | 2.9 | 9.2 | 6.8 |
| Operating income | $ 18.4 | $ 18.9 | $ 29.7 | $ 21.9 |
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- Definition The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- 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. No definition available.
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- Definition Changes in market value of common stock held by subsidiaries. No definition available.
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- Definition Amount of post retirement benefit plan cost (credit), classified as other. Includes, but not limited to defined benefit and defined contribution plans. No definition available.
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