Restructuring - Schedule of Restructuring Activities (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	$ 1,874	$ 5,078
Restructuring charges	66	5,431
Costs paid or otherwise settled	(1,360)	(6,978)
Balance at the end of the period	580	3,531
Severance & related
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	801	3,696
Restructuring charges	(248)	1,676
Costs paid or otherwise settled	(52)	(3,056)
Balance at the end of the period	501	2,316
Lease Termination
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	1,036	1,005
Restructuring charges	63	220
Costs paid or otherwise settled	(1,049)	(323)
Balance at the end of the period	50	902
Software Contracts & Engineering Tools
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	25	377
Restructuring charges	0	2,181
Costs paid or otherwise settled	(25)	(2,245)
Balance at the end of the period	0	313
Other
Restructuring Reserve [Roll Forward]
Balance at beginning of the period	12	0
Restructuring charges	251	1,354
Costs paid or otherwise settled	(234)	(1,354)
Balance at the end of the period	$ 29	$ 0