Balance Sheet Components (Schedule Of Goodwill By Segment) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill (period start)	$ 64,314
Goodwill from acquisition of Meural	16,407
Goodwill (period end)	80,721
Connected Home
Goodwill [Roll Forward]
Goodwill (period start)	28,035
Goodwill from acquisition of Meural	16,407
Goodwill (period end)	44,442
SMB
Goodwill [Roll Forward]
Goodwill (period start)	36,279
Goodwill from acquisition of Meural	0
Goodwill (period end)	$ 36,279

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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