Restructuring - Additional Information (Detail) - USD ($)	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Total restructuring reserve balance	$ 32,500,000	$ 36,000,000	$ 39,600,000	$ 43,700,000	$ 24,700,000	$ 35,800,000
Western Europe Restructuring Activities
Restructuring Cost and Reserve [Line Items]
Aggregate cost for restructuring initiatives	101,000,000
Remaining restructuring liability	29,000,000
Maximum
Restructuring Cost and Reserve [Line Items]
Aggregate cost for restructuring initiatives	28,000,000
Minimum
Restructuring Cost and Reserve [Line Items]
Aggregate cost for restructuring initiatives	$ 10,000,000