Reconciliation of Total Segment Profit to Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Apr. 01, 2017
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Segment Profit	$ 96,695	$ 68,075
Amortization	11,669	10,945
Unallocated General And Administrative Expenses	6,553	6,210
Operating income	78,473	50,920
Interest expense	8,159	8,473
Interest income	(933)	(80)
Other income, net	139	902
Income before income tax expense	$ 71,108	$ 41,625

Total segment profit

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General and administrative expenses not allocated to segment profit of company's business segments

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+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of interest income earned from interest bearing assets classified as other.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of income (expense) related to nonoperating activities, classified as other.

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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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