Retirement and Post Retirement Health Care Plans (Level 3 Plan Assets) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016
Change in Fair Value of Plan Assets:
Fair Value of Plan Assets at Beginning of Period	$ 160.3
Fair Value of Plan Assets at End of Period	185.3	$ 160.3
Level 3
Change in Fair Value of Plan Assets:
Fair Value of Plan Assets at Beginning of Period	10.0	8.1
Net Purchases (Sales)	(0.5)	1.7
Net Gains	0.1	0.2
Fair Value of Plan Assets at End of Period	9.6	10.0
Real Estate
Change in Fair Value of Plan Assets:
Fair Value	$ 9.6	$ 10.0
Real Estate \| Level 3 \| Minimum
Change in Fair Value of Plan Assets:
Fair Value Inputs, Exit Capitalization Rate	4.90%	4.90%
Fair Value Inputs, Discount Rate	6.60%	6.60%
Real Estate \| Level 3 \| Maximum
Change in Fair Value of Plan Assets:
Fair Value Inputs, Exit Capitalization Rate	7.00%	7.00%
Fair Value Inputs, Discount Rate	8.00%	8.00%

Fair Value Inputs, Exit Capitalization Rate

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ 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=82843861&loc=d3e1928-114920

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-Subparagraph (c)(1a)
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