v3.19.3.a.u2
Inventory - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Inventory [Line Items]      
Inventory write-downs $ 193 $ 85 $ 132
Cost of Revenues [Member]      
Inventory [Line Items]      
Inventory write-downs $ 138 $ 78 $ 124