Pension, Retiree Medical and Savings Plans (Effects of 1-Percentage-Point Change in the Assumed Health Care Trend Rate) (Details) $ in Millions	12 Months Ended
Dec. 27, 2014 USD ($)
General Discussion of Pension and Other Postretirement Benefits [Abstract]
One percent increase in 2013 service and interest cost components	$ 4
One percent decrease in 2013 service and interest cost components	(3)
One percent increase in 2013 benefit liability	46
One percent decrease in 2013 benefit liability	$ (40)

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (m)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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- References

No definition available.

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