SEGMENT INFORMATION - Summary of Unallocated Corporate Overhead (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Segment Reporting Information [Line Items]
Stock-based compensation	$ 13,547	$ 11,890	$ 24,088	$ 21,376
Unallocated corporate
Segment Reporting Information [Line Items]
Stock-based compensation	9,616	7,421	16,607	13,004
Compensation, benefits, and other employee-related expenses	15,315	10,365	35,911	24,746
External consulting and other service expenses	5,010	4,085	7,944	9,852
Information technology	3,190	3,617	5,654	6,010
Depreciation	1,585	2,102	3,419	4,090
Acquisition and integration	11,692	1,191	14,556	1,212
Other general unallocated corporate	1,865	3,505	4,262	6,291
Total unallocated corporate expense	$ 48,273	$ 32,286	$ 88,353	$ 65,205

Represents the sum total of audit, tax and related expenses.

No definition available.

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- Definition

Expenditures for salaries and bonuses for officers and non-officers. Does not include allocated share-based compensation, pension and post-retirement benefit expense.

+ References

No definition available.

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- Definition

Amount of direct costs of the business combination or disposition including legal, accounting, and other costs incurred to consummate the business acquisition or disposition.

+ References

No definition available.

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- Definition

Represents the amount of unallocated corporate expenses.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The amount of expense in the period for communications and data processing expense.

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-Name Accounting Standards Codification
-Topic 220
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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

Amount of general expenses not normally included in Other Operating Costs and Expenses.

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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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