Investment in TiO2 Manufacturing Joint Venture and Other Assets - Investment in TiO2 Manufacturing Joint Venture and Other Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Other assets:
Land held for development	$ 138.1	$ 157.2
Waste disposal site operating permits, net	42.9	48.1
Restricted cash equivalents	24.2	19.6
IBNR receivables	7.1	7.0
Capital lease deposit	6.2	6.2
Intangible assets		5.1
Other	17.9	11.8
Total	236.4	255.0
Waste Management
Other assets:
Restricted cash equivalents	21.6	16.2
Waste Management | Capitalized Operating Permits
Other assets:
Waste disposal site operating permits, net	$ 42.9	$ 48.1