Revenue (Schedule of Net Revenue Disaggregated by Geographical Region and Sales Channel) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Total net revenue	$ 265,858	$ 269,411	$ 745,792	$ 769,888
Service provider
Disaggregation of Revenue [Line Items]
Total net revenue	36,454	31,960	102,571	121,853
Non-service provider
Disaggregation of Revenue [Line Items]
Total net revenue	229,404	237,451	643,221	648,035
Americas
Disaggregation of Revenue [Line Items]
Total net revenue	178,679	175,932	483,878	510,358
EMEA
Disaggregation of Revenue [Line Items]
Total net revenue	49,554	53,158	149,608	148,801
APAC
Disaggregation of Revenue [Line Items]
Total net revenue	37,625	40,321	112,306	110,729
Connected Home
Disaggregation of Revenue [Line Items]
Total net revenue	190,672	194,683	527,532	555,422
Connected Home | Service provider
Disaggregation of Revenue [Line Items]
Total net revenue	35,482	30,769	99,201	118,899
Connected Home | Non-service provider
Disaggregation of Revenue [Line Items]
Total net revenue	155,190	163,914	428,331	436,523
Connected Home | Americas
Disaggregation of Revenue [Line Items]
Total net revenue	146,806	141,883	392,162	416,491
Connected Home | EMEA
Disaggregation of Revenue [Line Items]
Total net revenue	22,190	27,619	65,406	69,134
Connected Home | APAC
Disaggregation of Revenue [Line Items]
Total net revenue	21,676	25,181	69,964	69,797
SMB
Disaggregation of Revenue [Line Items]
Total net revenue	75,186	74,728	218,260	214,466
SMB | Service provider
Disaggregation of Revenue [Line Items]
Total net revenue	972	1,191	3,370	2,954
SMB | Non-service provider
Disaggregation of Revenue [Line Items]
Total net revenue	74,214	73,537	214,890	211,512
SMB | Americas
Disaggregation of Revenue [Line Items]
Total net revenue	31,873	34,049	91,716	93,867
SMB | EMEA
Disaggregation of Revenue [Line Items]
Total net revenue	27,364	25,539	84,202	79,667
SMB | APAC
Disaggregation of Revenue [Line Items]
Total net revenue	$ 15,949	$ 15,140	$ 42,342	$ 40,932