| **Financial Instruments Financial Instruments - Investments - Unrealized Gains and Losses Related to Equity Securities - Footnotes (Details) $ in Millions** | Mar. 29, 2020 USD ($) |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------|
| **Financial Instruments [Abstract]**                                                                                                                         |                  |
| Cumulative impairment losses and downward price adjustments on equity securities                                                                             | $ 58                  |
| Cumulative upward price adjustments on equity securities                                                                                                     | $ 60                  |

| X                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Equity Securities Without Readily Determinable Fair Value, Impairment Loss And Downward Price Adjustment, Cumulative Amount
+ References
No definition available.
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| X                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financial Instruments [Abstract]
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value.
+ References
Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117539-209714
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