Related Party Transactions - Current Receivables and Payables to Affiliates (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current receivables from affiliates:
Receivables from affiliates		$ 313
Current payables to affiliates:
Payable to affiliates	$ 691	725
Other - Trade Items
Current payables to affiliates:
Payable to affiliates	682	696
Valhi \| Income Taxes
Current payables to affiliates:
Payable to affiliates	$ 9	$ 29

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
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-URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant