Retirement Plans (Details 10) (Unobservable Inputs (Level 3), USD $) In Millions, unless otherwise specified			12 Months Ended
Dec. 28, 2013	Dec. 29, 2012	Dec. 28, 2013 Hedge funds	Dec. 28, 2013 Private equity partnerships	Dec. 28, 2013 Real estate
Reconciliation for fair value measurements that use significant unobservable inputs (Level 3)
Balance at beginning of year	$ 1,033	$ 920	$ 104	$ 308	$ 508
Actual return on plan assets:
Related to assets still held at reporting date			16	(5)	26
Related to assets sold during the period				44	23
Purchases, sales and settlements, net			55	(42)	(4)
Balance at end of year	$ 1,033	$ 920	$ 175	$ 305	$ 553

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Actual return on plan assets, separately identifying the amount related to assets sold during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

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Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

+ References

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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 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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

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Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(B)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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