Pension Plans, Postretirement and Other Employee Benefits - Pension Plan Assets Classes of Securities (Detail)	Dec. 31, 2016	Dec. 31, 2015
United States Pension Plans of US Entity, Defined Benefits | Equity Securities
Schedule of Pension and Other Postretirment Plan Assets by Fair Value [Line Items]
Debt Securities	70.00%	51.00%
United States Pension Plans of US Entity, Defined Benefits | Debt Securities
Schedule of Pension and Other Postretirment Plan Assets by Fair Value [Line Items]
Debt Securities	30.00%	49.00%
Foreign | Equity Securities
Schedule of Pension and Other Postretirment Plan Assets by Fair Value [Line Items]
Debt Securities	61.00%	61.00%
Foreign | Debt Securities
Schedule of Pension and Other Postretirment Plan Assets by Fair Value [Line Items]
Debt Securities	34.00%	30.00%
Foreign | Real Estate
Schedule of Pension and Other Postretirment Plan Assets by Fair Value [Line Items]
Debt Securities	2.00%	2.00%
Foreign | All Other
Schedule of Pension and Other Postretirment Plan Assets by Fair Value [Line Items]
Debt Securities	3.00%	7.00%