Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 27,352
Amortization of Intangible Assets	6,800	$ 8,600
Finite-Lived Intangible Assets, Gross	289,449		$ 289,449
Finite-Lived Intangible Assets, Accumulated Amortization	(175,415)		(168,369)
Finite-Lived Intangible Assets, Amortization Expense, Year Two	24,558
Finite-Lived Intangible Assets, Amortization Expense, Year Three	18,427
Finite-Lived Intangible Assets, Amortization Expense, Year Four	16,732
Finite-Lived Intangible Assets, Amortization Expense, Year Five	13,714
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	$ 13,251
Finite-Lived Intangible Assets, Net			114,034
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years 5 months	5 years 6 months
Finite-Lived Intangible Assets, Gross	$ 251,025		251,025
Finite-Lived Intangible Assets, Accumulated Amortization	$ (143,577)		(136,895)
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	0 months	0 months
Finite-Lived Intangible Assets, Gross	$ 13,550		13,550
Finite-Lived Intangible Assets, Accumulated Amortization	$ (13,550)		(13,550)
Developed Technology Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	4 years 7 months	4 years 9 months
Finite-Lived Intangible Assets, Gross	$ 24,874		24,874
Finite-Lived Intangible Assets, Accumulated Amortization	(18,288)		(17,924)
Tradenames And Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 577,456		$ 575,091