Assumptions to Determine Benefit Obligation and Net Periodic Benefit Cost (Detail)		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016		Dec. 31, 2015
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation discount rate		3.55%	4.15%
Benefit Obligation rate of increases in compensation level		2.65%	2.65%
Net periodic benefit cost discount rate		4.15%	4.50%		4.00%
Net periodic benefit cost rate of increases in compensation level		2.65%	2.65%		3.50%
Expected long-term rate of return on assets		7.08%	7.08%		7.08%
Non-U.S. Pension Plans | Minimum
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation discount rate	[1]	0.25%	0.50%
Benefit Obligation rate of increases in compensation level	[1]	2.00%	2.00%
Net periodic benefit cost discount rate	[1]	0.50%	0.50%		0.50%
Net periodic benefit cost rate of increases in compensation level	[1]	2.00%	2.25%		2.25%
Expected long-term rate of return on assets	[1]	1.50%	1.50%		2.60%
Non-U.S. Pension Plans | Maximum
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation discount rate		3.60%	3.90%	[1]
Benefit Obligation rate of increases in compensation level		5.00%	5.00%	[1]
Net periodic benefit cost discount rate	[1]	3.90%	4.10%		4.00%
Net periodic benefit cost rate of increases in compensation level	[1]	5.00%	5.00%		5.00%
Expected long-term rate of return on assets	[1]	6.00%	6.15%		6.15%

[1] The Non-U.S. weighted average plan ranges in the tables above have been prepared using significant plans only, which in total represent around 90% of the total Non-U.S. projected benefit obligation.