Investment in TiO2 Manufacturing Joint Venture and Other Assets - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Assets Non Current [Line Items]
Percentage owned manufacturing joint venture under equity method investment			50.00%
Operating lease expense			$ 7,600,000	$ 8,200,000	$ 15,000,000
Operating lease, right-of-use asset			2,500,000	1,600,000
Operating lease, liability			$ 2,500,000	$ 1,600,000
Weighted average remaining lease term			15 years	14 years
Weighted average discount rate associated with leases			4.80%	4.60%
Operating lease liability			$ 25,500,000
Operating lease not yet commenced, description			At December 31, 2020, we have no significant lease commitments that have not yet commenced.
Infrastructure reimbursement	$ 19,100,000	$ 8,800,000	$ 19,700,000	$ 9,200,000	4,300,000
City Of Henderson
Other Assets Non Current [Line Items]
Infrastructure reimbursement			$ 19,100,000	$ 8,800,000	$ 3,100,000
Annual interest rate				6.00%
City Of Henderson | Notes Payable
Other Assets Non Current [Line Items]
Debt instrument expiry year				2036
OPA | City of Henderson Redevelopment Agency
Other Assets Non Current [Line Items]
Tax increment reimbursement percentage			75.00%
OPA | Maximum | City of Henderson Redevelopment Agency
Other Assets Non Current [Line Items]
Reimbursement revenue			$ 209,000,000
Chemicals | Leverkusen TiO2 production facility
Other Assets Non Current [Line Items]
Operating lease liability			$ 7,600,000
LPC
Other Assets Non Current [Line Items]
Percentage owned manufacturing joint venture under equity method investment			50.00%
LPC | Chemicals
Other Assets Non Current [Line Items]
Percentage owned manufacturing joint venture under equity method investment			50.00%
Venator Materials PLC | Tioxide Group
Other Assets Non Current [Line Items]
Parent company ownership interest			100.00%