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Income Taxes (Narrative) (Details) - USD ($) $ in Millions			3 Months Ended		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Jun. 30, 2018	Dec. 30, 2017	Sep. 29, 2018
Federal corporate tax rate	21.00%	35.00%
Decrease in net deferred tax liabilities as a result of the decrease in the federal rate			$ 10.6	$ 26.7
Scenario, Plan [Member]
Blended federal corporate tax rate expected for fiscal year					24.50%

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- Definition

Blended Federal Corporate Tax Rate

+ References

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- Definition

Tax Cuts And Jobs Act Of 2017 Incomplete Accounting Change In Tax Rate Deferred Tax Liability Provisional Income Tax Benefit

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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