Shareholders' Equity (Schedule Of Share-Based Compensation Activity) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from the Exercise of Stock Options	$ 0.4	$ 0.5	$ 4.1
Options and SAR's
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of share-based incentive awards exercised	4.3	2.5	4.3
Proceeds from the Exercise of Stock Options	0.4	0.5	4.1
Total fair value of share-based incentive awards vested	$ 4.3	$ 4.9	$ 4.9

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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