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
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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Investments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Investments (Details) - USD ($) $ in Millions	Jul. 02, 2016	Jul. 04, 2015	Jul. 02, 2016	Jul. 04, 2015	Dec. 31, 2015
Investments
Total short term investments, amortized cost	$ 1,140		$ 1,140		$ 1,269
Total short term investments, fair value	1,143		1,143		1,254
Unrealized gains (losses) on trading securities	9	$ (2)	13	$ 3
Available-for-sale securities.
Investments
Amortized Cost	2		2		81
Fair Value	2		2		81
Money market funds
Investments
Amortized Cost	2		2		81
Fair Value	2		2		81
Trading securities.
Investments
Amortized Cost	1,138		1,138		1,188
Fair Value	1,141		1,141		1,173
Domestic equity securities
Investments
Amortized Cost	474		474		475
Fair Value	484		484		466
Domestic debt securities
Investments
Amortized Cost	396		396		452
Fair Value	398		398		450
Foreign equity securities
Investments
Amortized Cost	132		132		120
Fair Value	125		125		120
High yield trading debt securities
Investments
Amortized Cost	108		108		108
Fair Value	107		107		104
Collateralized loan obligation
Investments
Amortized Cost	14		14		10
Fair Value	13		13		10
Money market funds held in trading accounts
Investments
Amortized Cost	13		13		22
Fair Value	13		13		22
Other trading securities
Investments
Amortized Cost	1		1		1
Fair Value	1		1		1
Denominated in foreign currencies \| Money market funds
Investments
Fair Value	2		2		3
Denominated in foreign currencies \| Foreign equity securities
Investments
Fair Value	76		76		80
Denominated in Euros \| Foreign equity securities
Investments
Fair Value	23		23		25
Denominated in Japanese Yen \| Foreign equity securities
Investments
Fair Value	17		17		20
Denominated in British pounds \| Foreign equity securities
Investments
Fair Value	14		14		15
Denominated in Swiss Franc \| Foreign equity securities
Investments
Fair Value	6		6		7
Denominated in other foreign currencies \| Foreign equity securities
Investments
Fair Value	$ 16		$ 16		$ 13