Segment Information (Schedule of Reportable Segments and Reconciliation of Segment Contribution Income to Income Before Income Taxes) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total net revenue		$ 252,971	$ 265,858	$ 230,852	$ 249,082	$ 288,928	$ 269,411	$ 255,276	$ 245,201	$ 998,763	$ 1,058,816	$ 1,039,169
Total segment contribution income										135,057	166,482	147,735
Corporate and unallocated costs										(70,525)	(90,186)	(75,305)
Amortization of intangibles	[1]									(6,731)	(7,979)	(10,663)
Stock-based compensation expense										(29,137)	(26,461)	(18,969)
Separation expense										(264)	(929)	0
Change in fair value of contingent consideration										25	0	0
Restructuring and other charges										(2,077)	(2,198)	(97)
Litigation reserves, net										(160)	(15)	(148)
Interest income, net										2,539	3,980	2,114
Other income (expense), net										844	510	1,557
Income before income taxes										29,571	43,204	46,224
Connected Home
Segment Reporting Information [Line Items]
Total net revenue										711,391	771,060	768,261
Total segment contribution income										$ 67,775	$ 96,340	$ 83,870
Segment contribution margin										9.50%	12.50%	10.90%
SMB
Segment Reporting Information [Line Items]
Total net revenue										$ 287,372	$ 287,756	$ 270,908
Total segment contribution income										$ 67,282	$ 70,142	$ 63,865
Segment contribution margin										23.40%	24.40%	23.60%

[1] Amount excludes amortization expense related to patents within purchased intangibles in cost of revenue.