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Segment Information - Net Revenues by Product Segment and by Product Line (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Segment Reporting Information [Line Items] |  |  |
Net revenues | $ 8,347 | $ 6,973 | $ 6,897
Product Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net revenues | 8,318 | 6,945 | 6,874
Automotive and Discrete Group (ADG) [Member] | Product Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net revenues | 3,059 | 2,813 | 2,731
Analog, MEMS & Sensors Group (AMS) [Member] | Product Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net revenues | 2,613 | 1,847 | 1,851
Microcontrollers and Digital ICs Group (MDG) [Member] | Product Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net revenues | 2,646 | 2,285 | 2,292
Others [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net revenues | $ 29 | $ 28 | $ 23

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