Pension and Other Postretirement Benefits - Discount Rates and Weighted-Average Wage Increases Used to Determine the Benefit Obligations (Detail)	Dec. 31, 2014	Dec. 31, 2013
U.S. Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.10%	5.00%
Wage increases	4.00%	4.00%
Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.50%	4.50%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.00%	5.00%