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Commitments and Contingencies - Additional Information (Detail) |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Jul. 24, 2019 USD ($) defendant installment | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) installment | Dec. 31, 2019 USD ($) | Dec. 31, 2021 USD ($) site case | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Recognized accretion expense |  |  |  |  |  |  |  |  | $ 1,116,000 | $ 1,321,000 | $ 646,000 |
Long-term litigation settlement |  |  |  |  |  |  |  |  | 38,519,000 | 49,403,000 |  |
Litigation settlement expense |  |  |  |  |  |  |  |  |  |  | 19,266,000 |
Accrual for reasonably estimable environmental remediation and related matters |  |  |  |  |  |  |  | $ 94,508,000 | $ 92,940,000 | $ 93,416,000 | $ 94,508,000 | $ 98,211,000
Component Products | Customer Concentration Risk | Top Ten Customers | Sales Revenue |  |  |  |  |  |  |  |  |  |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Concentration risk percentage |  |  |  |  |  |  |  |  | 51.00% | 48.00% | 47.00% |
Component Products | Customer Concentration Risk | Customer Two | Sales Revenue | CompX Security Products Business |  |  |  |  |  |  |  |  |  |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Concentration risk percentage |  |  |  |  |  |  |  |  | 16.00% | 17.00% | 14.00% |
Environmental Remediation Sites NL Named As PRP Or Defendant |  |  |  |  |  |  |  |  |  |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Accrual for reasonably estimable environmental remediation and related matters |  |  |  |  |  |  |  |  | $ 93,000,000 |  |  |
Number of sites associated with remediation and related costs | site |  |  |  |  |  |  |  |  | 32 |  |  |
Number of sites currently not able to reasonably estimate a range of costs | site |  |  |  |  |  |  |  |  | 5 |  |  |
Maximum | Environmental Remediation Sites NL Named As PRP Or Defendant |  |  |  |  |  |  |  |  |  |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upper end range, estimate costs for remediation and related matters |  |  |  |  |  |  |  |  | $ 118,000,000 |  |  |
Environmental Remediation Litigation |  |  |  |  |  |  |  |  |  |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Recoveries receivable |  |  |  |  |  |  |  |  | $ 0 | $ 0 |  |
Lead Pigment Litigation |  |  |  |  |  |  |  |  |  |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Period by which loss contingency claims settled and dismissed |  |  |  |  |  |  |  |  | 30 years |  |  |
Description of defendants |  |  |  |  |  |  |  |  | on July 24, 2019, an order approving a global settlement agreement entered into among all of the plaintiffs and the three defendants remaining in the case (the Sherwin Williams Company, ConAgra Grocery Products and us) was entered by the court and the case was dismissed with prejudice. The global settlement agreement provides that an aggregate $305 million will be paid collectively by the three co-defendants in full satisfaction of all claims resulting in a dismissal of the case with prejudice and the resolution of (i) all pending and future claims by the plaintiffs in the case, and (ii) all potential claims for contribution or indemnity between us and our co-defendants in respect to the case |  |  |
Number of defendants | defendant | 3 |  |  |  |  |  |  |  |  |  |  |
Litigation settlement amount | $ 305,000,000 |  |  |  |  |  |  |  |  |  |  |
NL's portion of global settlement amount, gross value | 101,700,000 |  |  |  |  |  | $ 62,000,000 |  |  |  |  |
Litigation initial payment made 60 days after litigation settlement | 25,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Remaining litigation settlement charge | $ 76,700,000 |  |  |  |  |  | $ 20,000,000 |  |  |  |  |
Number of annual installments | installment | 6 |  |  |  |  |  | 5 |  |  |  |  |
Remaining litigation settlement payment due in first year | $ 12,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Remaining litigation settlement payment due in second year | 12,000,000 |  |  |  |  |  |  |  |  |  |  |
Remaining litigation settlement payment due in third year | 12,000,000 |  |  |  |  |  |  |  |  |  |  |
Remaining litigation settlement payment due in fourth year | 12,000,000 |  |  |  |  |  |  |  |  |  |  |
Remaining litigation settlement payment due in fifth year | 12,000,000 |  |  |  |  |  |  |  |  |  |  |
Remaining litigation settlement payment due in sixth year | 16,700,000 |  |  |  |  |  |  |  |  |  |  |
Escrow deposit | $ 9,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Litigation initial payment |  | $ 12,000,000.0 | $ 12,000,000.0 | $ 25,000,000.0 |  |  |  |  |  |  |  |
Recognized accretion expense |  |  |  |  |  |  |  | $ 600,000 | $ 1,100,000 | $ 1,300,000 |  |
Litigation settlement, current |  |  |  |  |  |  | $ 80,000,000 |  |  |  |  |
Litigation settlement charge upon approval of settlement terms |  |  |  |  |  |  | 45,000,000 |  |  |  |  |
Long-term litigation settlement |  |  |  |  |  |  | $ 17,000,000 |  |  |  |  |
Litigation settlement installments payment beginning term from approval |  |  |  |  |  |  | 4 years |  |  |  |  |
Discounted rate for estimated present value of remaining litigation amount |  |  |  |  |  |  |  | 1.90% |  |  | 1.90% |
Litigation settlement expense |  |  |  |  |  | $ 19,600,000 |  |  |  |  | $ 19,300,000 |
Litigation settlement credit |  |  |  |  | $ 300,000 |  |  |  |  |  |  |
Litigation settlement estimated net present value |  |  |  |  |  |  |  | $ 96,300,000 |  |  | $ 96,300,000 |
Lead Pigment Litigation | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of cases settled and dismissed and found not liable | case |  |  |  |  |  |  |  |  | 100 |  |  |

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