Investment in TiO2 Manufacturing Joint Venture and Other Assets - Other Noncurrent Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Other assets:
Land held for development	$ 96.0	$ 125.3
Operating lease right-of-use assets	26.1	29.0
Restricted cash and cash equivalents	37.8	33.0
IBNR receivables	37.1	8.5
Note receivables - OPA	25.3	8.8
Other	8.7	11.9
Total	$ 231.0	$ 216.5

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Estimated amount after valuation allowance of reinsurance recoverables, due from reinsurers for incurred claims not yet reported, and claims settlement expenses.

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