v3.10.0.1
Postretirement Benefit Plans - Summary of PME Multi-Employer Plan (Detail) - PME Multi-Employer Plan [Member]
$ in Millions
12 Months Ended
Dec. 31, 2018
USD ($)
Employee
Dec. 31, 2017
USD ($)
Employee
Dec. 31, 2016
USD ($)
Employee
Multiemployer Plans [Line Items]      
NXP’s contributions to the plan $ 34 $ 35 $ 36
(including employees’ contributions) $ 4 $ 4 $ 4
Average number of NXP’s active employees participating in the plan | Employee 2,183 2,271 2,415