Employee Retirement Plans and Postretirement Benefits Net Periodic Pension (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 29, 2012
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the period	$ 16.1us-gaap_DefinedBenefitPlanServiceCost	$ 19.2us-gaap_DefinedBenefitPlanServiceCost	$ 19.7us-gaap_DefinedBenefitPlanServiceCost
Interest cost on projected benefit obligation	174.7us-gaap_DefinedBenefitPlanInterestCost	164.2us-gaap_DefinedBenefitPlanInterestCost	173.7us-gaap_DefinedBenefitPlanInterestCost
Expected return on plan assets	(195.6)	(177.9)	(175.2)
Amortization of prior service costs (benefits)	(2.4)	(2.8)	(2.9)
Amortization of net actuarial loss (gain)	35.4	56.5	39.2
Curtailment loss	0	0	1.3
Special termination benefits	0	0	0.4
Expected Participant Contributions	(1.0)	(1.2)	(1.5)
Net periodic pension cost (benefit)	27.2	58.0	54.7
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the period	13.1	15.8	16.8
Interest cost on projected benefit obligation	167.6	157.0	165.7
Expected return on plan assets	(195.6)	(177.9)	(175.2)
Amortization of prior service costs (benefits)	0.6	0.8	0.8
Amortization of net actuarial loss (gain)	36.3	56.6	39.4
Curtailment loss	0	0	1.3
Special termination benefits	0	0	0.4
Expected Participant Contributions	(1.0)	(1.2)	(1.5)
Net periodic pension cost (benefit)	21.0	51.1	47.7
OPEB
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the period	3.0	3.4	2.9
Interest cost on projected benefit obligation	7.1	7.2	8.0
Expected return on plan assets	0	0	0
Amortization of prior service costs (benefits)	(3.0)	(3.6)	(3.7)
Amortization of net actuarial loss (gain)	(0.9)	(0.1)	(0.2)
Curtailment loss	0	0	0
Special termination benefits	0	0	0
Expected Participant Contributions	0	0	0
Net periodic pension cost (benefit)	$ 6.2	$ 6.9	$ 7.0

The amount of expected participant and National Insurance contributions.

No definition available.

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- Definition

The amount recognized in net period benefit cost related to special termination benefits offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time.

+ References

No definition available.

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- Definition

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

+ References

+ Details

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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

+ Details

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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

-URI http://asc.fasb.org/extlink&oid=6512136

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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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.

+ References

+ Details

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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 amount of net gain (loss) recognized in net periodic benefit cost as a result of an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ 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 (h)(7)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Plan Curtailment

-URI http://asc.fasb.org/extlink&oid=6520938

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 15

-Paragraph 6

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

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

-URI http://asc.fasb.org/extlink&oid=6525008

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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