Retirement Benefits (Net Postretirement Health Care Benefits Plan) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 30, 2013	Mar. 31, 2012
Defined Contribution Plans [Abstract]
Company discretionary matching contributions	$ 0
Postretirement Health Care Benefits Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1
Interest cost	3	5
Expected return on plan assets	(2)	(3)
Amortization of:
Amortization of unrecognized net loss	4	3
Amortization of unrecognized prior service cost	(11)	0
Net postretirement health care expense (benefits)	$ (5)	$ 6
Minimum age of participants to be paid under retiree health reimbursement account	65 years
Prior service cost amortization period	3 years

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Pension And Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), Amortization Period

+ References

No definition available.

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- Definition

Retiree Health Reimbursement Account, Participant Minimum Age

+ References

No definition available.

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- Definition

The amount of gains or losses recognized in net periodic benefit cost.

+ References

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- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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