Commitments and Contingencies - Lead Pigment Litigation-NL and Environmental Matters and Litigation - Additional Information (Detail) $ in Millions		1 Months Ended	9 Months Ended
	Jul. 24, 2019 USD ($) Installment	Sep. 30, 2021 USD ($) site	Sep. 30, 2021 USD ($) Cases site	Dec. 31, 2020 USD ($)
Commitments And Contingent Liabilities [Line Items]
Accrual for reasonably estimable environmental remediation and related matters		$ 97.8	$ 97.8	$ 98.6
Other Environmental Cleanup Matters
Commitments And Contingent Liabilities [Line Items]
Accrual for reasonably estimable environmental remediation and related matters		5.0	5.0
NL | Environmental Remediation Sites NL Named As PRP Or Defendant
Commitments And Contingent Liabilities [Line Items]
Accrual for reasonably estimable environmental remediation and related matters		$ 93.0	$ 93.0
Number of sites associated with remediation and related costs | site		32	32
Number of sites for which NL not currently able to reasonably estimate range of costs | site		5	5
NL | 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		$ 112.0	$ 112.0
Lead Pigment Litigation | NL
Commitments And Contingent Liabilities [Line Items]
Number of cases settled and dismissed and found not liable | Cases			100
Period by which loss contingency claims settled and dismissed			30 years
C A Lead Paint Litigation | NL
Commitments And Contingent Liabilities [Line Items]
Number of annual installment payments | Installment	4
Litigation payment		$ 12.0
Remaining litigation settlement charge due in first installment	$ 12.0
Remaining litigation settlement charge due in second installment	12.0
Remaining litigation settlement charge due in third installment	12.0
Remaining litigation settlement charge due in fourth installment	$ 16.7