Segment information - Differences Between Segment Profit and Amounts Included in Net Income (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
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| Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] | ||||
| Net sales | $ 40,366 | $ 35,887 | $ 80,638 | $ 73,858 |
| Segment profit | 1,011 | 9,755 | 2,310 | 18,058 |
| Corporate expenses | (3,519) | (4,290) | (6,240) | (6,649) |
| Equity in earnings (losses) of Kronos Worldwide, Inc. | (2,811) | 5,973 | 2,714 | 8,449 |
| Interest and dividend income | 1,504 | 2,678 | 3,542 | 5,229 |
| Marketable equity securities | (108) | 779 | (8,659) | 3,162 |
| Other components of net periodic pension and OPEB cost | (285) | (318) | (570) | (636) |
| Interest expense | (90) | (148) | (666) | (293) |
| Income tax (expense) benefit | 43 | (1,302) | 66 | (2,290) |
| Net income | 1,054 | 8,453 | 2,376 | 15,768 |
| Single reportable segment | ||||
| Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] | ||||
| Net sales | 40,366 | 35,887 | 80,638 | 73,858 |
| Segment profit | 6,320 | 5,081 | 12,189 | 8,796 |
| Corporate expenses | (3,519) | (4,290) | (6,240) | (6,649) |
| Equity in earnings (losses) of Kronos Worldwide, Inc. | (2,811) | 5,973 | 2,714 | 8,449 |
| Interest and dividend income | 1,504 | 2,678 | 3,542 | 5,229 |
| Marketable equity securities | (108) | 779 | (8,659) | 3,162 |
| Other components of net periodic pension and OPEB cost | (285) | (318) | (570) | (636) |
| Interest expense | (90) | (148) | (666) | (293) |
| Income tax (expense) benefit | 43 | (1,302) | 66 | (2,290) |
| Net income | $ 1,054 | $ 8,453 | $ 2,376 | $ 15,768 |
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- Definition The aggregate total of income (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. No definition available.
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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/2009/role/commonPracticeRef
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- Definition Amount of income (loss) for proportionate share of equity method investee's income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of interest expense classified as nonoperating. 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 and dividend income on nonoperating securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of realized and unrealized gain (loss) on investment in marketable security. No definition available.
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- Definition Amount of cost (reversal of cost) for pension and other postretirement benefits. No definition available.
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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/disclosureRef
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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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- Details
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