Fair Value Measurements - Schedule of Investment Maturities (Details) (Fair Value, USD $) In Millions, unless otherwise specified	Mar. 27, 2015	Dec. 26, 2014
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Less than 1 year	$ 257	$ 292
1 - 2 years	12	45
2 - 5 years	80	100
Greater than 5 years	9	16
Total	$ 358	$ 453

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

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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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.

+ Details

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