Segment Information (Schedule of Reportable Segments and Reconciliation of Segment Contribution Income to Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Apr. 01, 2018
Segment Reporting Information [Line Items]
Total net revenue	$ 249,082	$ 245,201
Total segment contribution income	41,804	32,734
Corporate and unallocated costs	(19,132)	(22,298)
Amortization of intangibles	(2,010)	(2,079)
Stock-based compensation expense	(6,458)	(6,864)
Separation expense	(264)	0
Restructuring and other charges	68	9
Interest income	701	748
Other income (expense), net	341	(1,318)
Income before income taxes	15,050	932
Connected Home
Segment Reporting Information [Line Items]
Total net revenue	169,365	174,315
Total segment contribution income	$ 19,119	$ 16,212
Segment contribution margin	11.30%	9.30%
SMB
Segment Reporting Information [Line Items]
Total net revenue	$ 79,717	$ 70,886
Total segment contribution income	$ 22,685	$ 16,522
Segment contribution margin	28.50%	23.30%

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Corporate and unallocated costs

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Restructuring and other charges not specified within the taxonomy.

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Total segment contribution income

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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