Commitments and Contingencies - Additional Information (Detail) $ in Millions	Dec. 31, 2016 USD ($) LegalMatter	Dec. 31, 2015 USD ($)
Loss Contingencies [Line Items]
Number Of Claims In Lawsuit | LegalMatter	3,800
Environmental Reserve	$ 18.3	$ 22.8
Outstanding Value Of Letters Of Credit	$ 331.0	402.2
Valves And Controls [Member]
Loss Contingencies [Line Items]
Number Of Claims In Lawsuit | LegalMatter	3,300
Liability For claims and contingencies	$ 228.3	237.9
Liability reserve for insurance claims	108.5	111.0
Outstanding Value Of Letters Of Credit	$ 156.6	$ 202.3