Investments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Sep. 28, 2019	Jun. 30, 2020	Dec. 28, 2019
Investments [Abstract]
Proceeds from Sale of Available-for-sale Securities		$ 5	$ 181
Equity Securities without Readily Determinable Fair Value, Amount	$ 320	320			$ 314
Equity Securities, FV-NI				$ 41	14
Equity Securities, FV-NI, Unrealized Gain	49	76	$ 9
Equity Method Investments	$ 11	11			$ 9
Proceeds from Sale of Equity Securities with Readily Determinable Fair Values		$ 90

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1A
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in equity security without readily determinable fair value.

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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- Definition

The cash inflow associated with the sale of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

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