Restructuring (Details) - USD ($) $ in Thousands	6 Months Ended
	Jul. 02, 2016	Jul. 04, 2015
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	$ 5,078	$ 182
Restructuring charges	7,999	8,962
Costs paid or otherwise settled	(9,859)	(5,554)
Balance at the end of the period	3,218	3,590
Severance and related
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	3,696	0
Restructuring charges	1,878	6,909
Costs paid or otherwise settled	(4,406)	(4,503)
Balance at the end of the period	1,168	2,406
Lease Termination
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	1,005	43
Restructuring charges	2,234	688
Costs paid or otherwise settled	(1,402)	(313)
Balance at the end of the period	1,837	418
Software Contracts & Engineering Tools
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	377	0
Restructuring charges	1,931	1,303
Costs paid or otherwise settled	(2,111)	(537)
Balance at the end of the period	197	766
Other
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	0	139
Restructuring charges	1,956	62
Costs paid or otherwise settled	(1,940)	(201)
Balance at the end of the period	$ 16	$ 0