Long-Term Debt - Long-Term Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Long-term debt
Total debt	$ 533.4	$ 559.5
Less current maturities	1.4	1.8
Total long-term debt	532.0	557.7
VALHI, INC. \| Contran Credit Facility
Long-term debt
Total debt	97.7	121.4
Kronos Worldwide, Inc. \| 3.75% Senior Secured Notes due September 15, 2025 \| Kronos International, Inc
Long-term debt
Total debt	422.5	424.1
LandWell \| Unsecured Debt \| Western Alliance Bank
Long-term debt
Total debt	12.5	12.9
Other Subsidiary \| Other
Long-term debt
Total debt	0.7	1.1
Subsidiary
Long-term debt
Total debt	$ 435.7	$ 438.1

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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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