Investment in TiO2 Manufacturing Joint Venture and Other Assets - Other Noncurrent Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Other assets:
Restricted cash and cash equivalents	$ 41.9	$ 37.8
Note receivables - OPA	38.7	25.3
Land held for development	36.0	96.0
IBNR receivables	34.4	37.1
Operating lease right-of-use assets	$ 19.9	$ 26.1
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Total	Total
Restricted Cash and Cash Equivalents, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Total	Total
Other	$ 16.8	$ 8.7
Total	$ 187.7	$ 231.0