Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 26, 2016	Dec. 26, 2015	Dec. 27, 2014
Other intangible assets
Gross	$ 525,900		$ 533,661
Accumulated Amortization	(260,516)		(252,857)
Net	265,384		$ 280,804
Impairment charge	1,900
Backlog
Other intangible assets
Gross	51,537	$ 50,568
Accumulated Amortization	(51,526)	(50,554)
Net	11	14
Technology
Other intangible assets
Gross	56,725	60,350
Accumulated Amortization	(6,462)	(5,911)
Net	50,263	54,439
Trademarks and trade names
Other intangible assets
Gross	11,187	11,495
Accumulated Amortization	(6,076)	(5,944)
Net	5,111	5,551
Other
Other intangible assets
Gross	14,722	14,711
Accumulated Amortization	(7,611)	(7,285)
Net	7,111	7,426
Other intangible assets
Other intangible assets
Gross	134,171	137,124
Accumulated Amortization	(71,675)	(69,694)
Net	62,496	67,430
Client relationships
Other intangible assets
Gross	391,729	396,537
Accumulated Amortization	(188,841)	(183,163)
Net	$ 202,888	$ 213,374

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

+ References

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=26713463&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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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

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