Pensions and Postretirement Benefits Other than Pensions - Weighted Average Assumptions Used to Determine Benefit Obligations (Detail)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	3.70%	3.20%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	4.05%	3.50%
United States | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	4.05%	3.50%
United States | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	4.05%	3.50%
Foreign Plan | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	2.80%	2.50%
Foreign Plan | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	0.00%	0.00%