Fair Value Measurements - Schedule of Investment Maturities (Details) - Fair Value - USD ($) $ in Millions	Dec. 31, 2017	Dec. 30, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Less than 1 year	$ 18	$ 417
1 - 2 years	3	12
2 - 5 years	8	4
Greater than 5 years	66	67
Investments at fair value	$ 95	$ 500

Available-for-sale Securities, Debt Maturities, Rolling Year One Through Two, Fair Value

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- Definition

Available-for-sale Securities, Debt Maturities, Rolling after Year Five, Fair Value

+ References

No definition available.

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- Definition

Fair value of available-for-sale debt securities maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Fair value of available-for-sale debt securities maturing in the second through fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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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.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 35
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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.7-03(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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