Long-Term Debt - Long-Term Debt (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Long-term debt
Total debt	$ 561.5	$ 559.5
Less current maturities	1.6	1.8
Total long-term debt	559.9	557.7
VALHI, INC. \| Contran Credit Facility
Long-term debt
Total debt	114.2	121.4
Kronos Worldwide, Inc. \| 3.75% Senior Secured Notes due September 15, 2025 \| Kronos International, Inc
Long-term debt
Total debt	433.5	424.1
LandWell \| Unsecured Debt \| Western Alliance Bank
Long-term debt
Total debt	12.9	12.9
Other Subsidiary \| Other
Long-term debt
Total debt	0.9	1.1
Subsidiary
Long-term debt
Total debt	$ 447.3	$ 438.1

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

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-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(22))
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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