Cumulative Effect of New Accounting Principle in Period of Adoption, Increase (Decrease) to AOCI.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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- Definition

The increase (decrease) in stockholders' equity during the period.

+ References

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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Summary of Significant Accounting Policies Narrative (Details) - USD ($) $ in Millions		9 Months Ended		12 Months Ended
	Jan. 01, 2018	Sep. 27, 2019	Sep. 28, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019
Business Acquisition [Line Items]
Net decrease to beginning parent's equity	$ 8.0
Operating lease ROU assets		$ 201.8					$ 182.0
Total operating lease liabilities		$ 213.8					$ 191.0
Effect of change in accounting principle on net other income, increase (decrease) to AOCI	(0.2)
Customer Concentration Risk
Business Acquisition [Line Items]
Concentration risk, percentage		10.00%		10.00%
Customer Concentration Risk \| Revenue Benchmark
Business Acquisition [Line Items]
Concentration risk, percentage		12.00%	12.00%	14.00%	15.00%	16.00%
Customer Concentration Risk \| Accounts Receivable
Business Acquisition [Line Items]
Concentration risk, percentage				8.00%	11.00%
Accounting Standards Update 2018-02
Business Acquisition [Line Items]
Effect of change in accounting principle on retained earnings	0.2
Effect of change in accounting principle on net other income, increase (decrease) to AOCI	$ (2.0)
Allowance for Doubtful Accounts
Business Acquisition [Line Items]
Charged to Costs & Expenses				$ 4.7	$ 5.8	$ 3.5