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Segment Information - Operating Income by Reportable Segment (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | $ 1,203 | $ 1,400 | $ 1,005
Product Segments [Member] |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | 1,307 | 1,466 | 1,060
Analog, MEMS & Sensors Group (AMS) [Member] | Product Segments [Member] |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | 596 | 488 | 364
Operating Segments [Member] |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | 1,307 | 1,466 | 1,060
Operating Segments [Member] | Automotive and Discrete Group (ADG) [Member] | Product Segments [Member] |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | 357 | 431 | 291
Operating Segments [Member] | Microcontrollers and Digital ICs Group (MDG) [Member] | Product Segments [Member] |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | 354 | 547 | 405
Segment Reconciling Items [Member] |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | (104) | (66) | (55)
Segment Reconciling Items [Member] | Others [Member] |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Operating income (loss) | $ (104) | $ (66) | $ (55)

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