Investments, Trading Assets (Detail) - Debt Securities [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)	$ 347	$ 117	$ 183	$ 99
Unrealized Gain (Loss) on Derivatives	$ 251	$ 102	$ 204	$ (104)

Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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