Assumptions to Determine Benefit Obligation and Net Periodic Benefit Cost (Detail) - Pension Plans, Defined Benefit		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation discount rate		2.35%	3.25%
Benefit Obligation rate of increases in compensation level		2.65%	2.65%
Net periodic benefit cost discount rate		3.25%	4.35%	3.55%
Net periodic benefit cost rate of increases in compensation level		2.65%	2.65%	2.65%
Expected long-term rate of return on assets		5.05%	5.05%	7.08%
Non-U.S. Pension Plans | Minimum
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation discount rate	[1]	0.25%	0.25%
Benefit Obligation rate of increases in compensation level	[1]	1.80%	2.00%
Net periodic benefit cost discount rate	[1]	0.25%	0.50%	0.25%
Net periodic benefit cost rate of increases in compensation level	[1]	2.00%	2.00%	2.00%
Expected long-term rate of return on assets	[1]	1.50%	2.25%	2.25%
Non-U.S. Pension Plans | Maximum
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation discount rate	[1]	2.70%	2.70%
Benefit Obligation rate of increases in compensation level	[1]	4.00%	5.00%
Net periodic benefit cost discount rate	[1]	2.70%	3.25%	3.25%
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]	2.25%	2.50%	2.50%

[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 83% of the total Non-U.S. projected benefit obligation.