Employee Benefit Plans (Plan Assets) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 25, 2015	Dec. 26, 2014
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 2,309	$ 2,504
Percent of Total Assets	100.00%	100.00%
Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Targeted and established equity allocation (in hundredths)	70.00%
Targeted allocation of total plan assets in domestic equity (in hundredths)	42.00%
Targeted allocation of total plan assets in international equity (in hundredths)	28.00%
Percentage within which the planned allocation is managed (in hundredths)	3.00%
Amount	$ 1,626	$ 1,715
Percent of Total Assets	70.00%	68.00%
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Targeted and established equity allocation (in hundredths)	30.00%
Amount	$ 641	$ 740
Percent of Total Assets	28.00%	30.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 42	$ 49
Percent of Total Assets	2.00%	2.00%

Target allocation percentage of investments in equity securities to total plan assets in domestic equity.

No definition available.

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- Definition

Target allocation percentage of investments in equity securities to total plan assets in international equity.

+ References

No definition available.

+ Details

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- Definition

Target allocation percentage of investments in within which plan assets investment are managed.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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