Retirement Plans (Schedule of Actual and Target Allocations of Plan Assets) (Details) - Pensions [Member]	12 Months Ended
Dec. 31, 2016	Jan. 02, 2016
Equity [Member]
Target Allocations [Abstract]
Target plan asset allocations range, minimum (percent)	60.00%
Target plan asset allocations range, maximum (percent)	75.00%
Fixed income [Member]
Target Allocations [Abstract]
Target plan asset allocations range, minimum (percent)	25.00%
Target plan asset allocations range, maximum (percent)	35.00%
Alternative and other investments [Member]
Target Allocations [Abstract]
Target plan asset allocations range, minimum (percent)	10.00%
Target plan asset allocations range, maximum (percent)	30.00%
Minimum [Member] \| Equity [Member]
Target Allocations [Abstract]
Actual plan asset allocations (percent)	52.00%	49.00%
Minimum [Member] \| Fixed income [Member]
Target Allocations [Abstract]
Actual plan asset allocations (percent)	26.00%	29.00%
Minimum [Member] \| Alternative and other investments [Member]
Target Allocations [Abstract]
Actual plan asset allocations (percent)	5.00%	5.00%
Maximum [Member] \| Equity [Member]
Target Allocations [Abstract]
Actual plan asset allocations (percent)	61.00%	62.00%
Maximum [Member] \| Fixed income [Member]
Target Allocations [Abstract]
Actual plan asset allocations (percent)	34.00%	33.00%
Maximum [Member] \| Alternative and other investments [Member]
Target Allocations [Abstract]
Actual plan asset allocations (percent)	22.00%	22.00%

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Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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