Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020	Dec. 31, 2020
Total investment gains (losses)	$ 128	$ 3	$ 330	$ (10)
Realized investment gains (losses)	10	0	48	0
Unrealized investment gains (losses)	118	$ 3	282	$ (10)
Partnership
Equity method investments	$ 1,200		$ 1,200		$ 453

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Balance Type:	debit
Period Type:	instant