GOODWILL AND INTANGIBLE ASSETS - Intangible Assets, Net by Major Class (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 26, 2015
Finite-lived intangible assets
Gross	$ 623,870	$ 533,661
Accumulated Amortization	(229,422)	(252,857)
Net	394,448	280,804
Backlog
Finite-lived intangible assets
Gross	8,370	50,568
Accumulated Amortization	(6,390)	(50,554)
Net	1,980	14
Technology
Finite-lived intangible assets
Gross	71,425	60,350
Accumulated Amortization	(14,314)	(5,911)
Net	57,111	54,439
Trademark and trade names
Finite-lived intangible assets
Gross	8,177	11,495
Accumulated Amortization	(4,124)	(5,944)
Net	4,053	5,551
Other
Finite-lived intangible assets
Gross	16,775	14,711
Accumulated Amortization	(5,628)	(7,285)
Net	11,147	7,426
Other intangible assets
Finite-lived intangible assets
Gross	104,747	137,124
Accumulated Amortization	(30,456)	(69,694)
Net	74,291	67,430
Client relationships
Finite-lived intangible assets
Gross	519,123	396,537
Accumulated Amortization	(198,966)	(183,163)
Net	$ 320,157	$ 213,374

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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