The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 1.9	$ 0.0	$ 1.9	$ 0.0
Expected amortization expense, year 1	8.5		8.5
Expected amortization expense, year 2	8.5		8.5
Expected amortization expense, year 3	8.5		8.5
Expected amortization expense, year 4	8.5		8.5
Expected amortization expense, year 5	$ 8.5		$ 8.5
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Useful lives			12 years
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Useful lives			4 years
Trade Names
Finite-Lived Intangible Assets [Line Items]
Useful lives			3 years
Favorable Leasehold Interest
Finite-Lived Intangible Assets [Line Items]
Useful lives			12 years
Cedar Creek
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired			$ 36.1