Line items represent reporting 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

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- Definition

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

+ References

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=82897076&loc=d3e27357-111563

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- Definition

Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(4))
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-SubTopic 210
-Section S99
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-SubTopic 210
-Section S99
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(g))
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-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

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Investments (Details) - USD ($) $ in Millions	3 Months Ended
Investments (Details) - USD ($) $ in Millions	Mar. 30, 2019	Mar. 31, 2018	Dec. 31, 2018
Investments
Total trading short-term investments	$ 1,488		$ 1,336
Change in unrealized gains (losses) on trading securities	104	$ (22)
Domestic equity securities
Investments
Fair Value	714		632
Domestic debt securities
Investments
Fair Value	396		268
Foreign equity securities
Investments
Fair Value	222		218
Foreign equity securities \| Denominated in foreign currencies
Investments
Fair Value	57		66
Foreign equity securities \| Denominated in Euros
Investments
Fair Value	27		25
Foreign equity securities \| Denominated in Japanese Yen
Investments
Fair Value	11		20
Foreign equity securities \| Denominated in British pounds
Investments
Fair Value	9		9
Foreign equity securities \| Denominated in Swiss Franc
Investments
Fair Value	3		3
Foreign equity securities \| Denominated in other foreign currencies
Investments
Fair Value	7		9
High yield securities
Investments
Fair Value	65		19
Foreign debt securities
Investments
Fair Value	40		16
Collateralized loan obligation
Investments
Fair Value	27		28
Money market funds held in trading accounts
Investments
Fair Value	10		146
Term deposits
Investments
Fair Value	9		9
Other trading securities
Investments
Fair Value	5
Money market funds \| Denominated in foreign currencies
Investments
Fair Value			$ 10
Money market funds \| Denominated in foreign currencies \| Maximum
Investments
Fair Value	$ 1