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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Significant Accounting Policies [Line Items] |  |  |
Net income tax payments (received) | $ (118,000) | $ (1,716,000) | $ 3,109,000
Received net refunds for income taxes | $ 200,000 | 1,700,000 |
Uncertain tax positions | 50.00% |  |
Advertising costs | $ 0 | 0 | 0
Research, development and certain sales technical support costs | 0 | 0 | $ 0
Environmental Remediation Litigation |  |  |
Significant Accounting Policies [Line Items] |  |  |
Recoveries receivable | $ 0 | $ 15,000,000 |
Minimum | Building |  |  |
Significant Accounting Policies [Line Items] |  |  |
Property and equipment, estimated useful lives | 15 years |  |
Minimum | Equipment and Software |  |  |
Significant Accounting Policies [Line Items] |  |  |
Property and equipment, estimated useful lives | 3 years |  |
Maximum | Building |  |  |
Significant Accounting Policies [Line Items] |  |  |
Property and equipment, estimated useful lives | 40 years |  |
Maximum | Equipment and Software |  |  |
Significant Accounting Policies [Line Items] |  |  |
Property and equipment, estimated useful lives | 20 years |  |
Kronos |  |  |
Significant Accounting Policies [Line Items] |  |  |
Parent company ownership interest | 30.00% |  |
CompX |  |  |
Significant Accounting Policies [Line Items] |  |  |
Percentage of controlling interest owned | 14.00% |  |
Parent Company | Valhi Inc |  |  |
Significant Accounting Policies [Line Items] |  |  |
Parent company ownership interest | 83.00% |  |
Parent Company | Contran Corporation |  |  |
Significant Accounting Policies [Line Items] |  |  |
Parent company ownership interest | 92.00% |  |

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- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 720 -SubTopic 35 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848 + Details
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