Commitments and contingencies - Lead Pigment Litigation-NL and Environmental Matters and Litigation - Additional Information (Details)	1 Months Ended	3 Months Ended
	Feb. 28, 2025 USD ($) company	Mar. 31, 2025 USD ($) site	Dec. 31, 2024 USD ($)
Commitments And Contingent Liabilities [Line Items]
Litigation settlement		$ 16,500,000	$ 16,400,000
Accrual for reasonably estimable environmental remediation and related matters		18,200,000	74,600,000
Other Environmental Cleanup Matters
Commitments And Contingent Liabilities [Line Items]
Accrual for reasonably estimable environmental remediation and related matters		5,000,000
Raritan Bay Slag Superfund Site
Commitments And Contingent Liabilities [Line Items]
Settlement amount	$ 151,100,000
Number of private companies to pay to resolve all federal and state law claims | company	22
NL Industries
Commitments And Contingent Liabilities [Line Items]
Settlement interest		500,000
Litigation payment		56,100,000
Litigation settlement, current		9,600,000
Aggregate income			$ 31,400,000
Insurance recoveries		0
NL Industries | Environmental Remediation Sites NL Named As PRP Or Defendant
Commitments And Contingent Liabilities [Line Items]
Accrual for reasonably estimable environmental remediation and related matters		$ 13,000,000
Number of sites associated with remediation and related costs		29
Number of sites for which NL not currently able to reasonably estimate range of costs | site		5
NL Industries | 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		$ 38,000,000
C A Lead Paint Litigation | NL Industries
Commitments And Contingent Liabilities [Line Items]
Remaining litigation settlement charge due in sixth installment		$ 16,700,000