Long-term debt (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Long-term debt
Total debt	$ 546.5	$ 559.5
Less current maturities	0.7	1.8
Total long-term debt	545.8	557.7
VALHI, INC. \| Contran Credit Facility
Long-term debt
Total debt	93.4	121.4
Kronos Worldwide, Inc. \| 3.75% Senior Secured Notes due September 15, 2025 \| Kronos International, Inc
Long-term debt
Total debt	440.9	424.1
LandWell \| Unsecured Debt \| Western Alliance Bank
Long-term debt
Total debt	12.2	12.9
Other Subsidiary \| Other
Long-term debt
Total debt		1.1
Subsidiary
Long-term debt
Total debt	$ 453.1	$ 438.1

Amount of long-term debt and lease obligation, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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