|**Other (Income)/Deductions - Net - Footnotes (Detail) - USD ($) $ in Millions**                                                                                                                                                                                                                                                                                                                                | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                              | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                             
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|**Loss Contingencies [Line Items]**                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                            
|Unrealized gain (loss) on equity securities                                                                                                                                                                                                                                                                                                                                                                     | [1]                                                                                                                                                                                                                                                                                                                                                                                                         | $ (610)                                                                                                                                                                                                                                                                                                                                                                                                    
|BioNTech and Cerevel [Member]                                                                                                                                                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                            
|**Loss Contingencies [Line Items]**                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                            
|Unrealized gain (loss) on equity securities                                                                                                                                                                                                                                                                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                             | $ (432)                                                                                                                                                                                                                                                                                                                                                                                                    
|BioNTech [Member] | Collaborative Arrangement [Member]                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                            
|**Loss Contingencies [Line Items]**                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                            
|Proceeds from collaborators                                                                                                                                                                                                                                                                                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                            
|                                                                                                                                                                                                                                                                                                                                                                                                               
|[1]
Included in net unrealized (gains)/losses are observable price changes on equity securities without readily determinable fair values. As of July 3, 2022, there were cumulative impairments and downward adjustments of $108 million and upward adjustments of $194 million. Impairments, downward and upward adjustments were not significant in the second quarter and first six months of 2022 and 2021. | [1]                                                                                                                                                                                                                                                                                                                                                                                                         | Included in net unrealized (gains)/losses are observable price changes on equity securities without readily determinable fair values. As of July 3, 2022, there were cumulative impairments and downward adjustments of $108 million and upward adjustments of $194 million. Impairments, downward and upward adjustments were not significant in the second quarter and first six months of 2022 and 2021.
|[1]                                                                                                                                                                                                                                                                                                                                                                                                             | Included in net unrealized (gains)/losses are observable price changes on equity securities without readily determinable fair values. As of July 3, 2022, there were cumulative impairments and downward adjustments of $108 million and upward adjustments of $194 million. Impairments, downward and upward adjustments were not significant in the second quarter and first six months of 2022 and 2021.

X- DefinitionAmount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).
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