Changes in Carrying Values of Goodwill (Detail) $ in Thousands	9 Months Ended
Sep. 29, 2018 USD ($)
Goodwill [Line Items]
Beginning balance	$ 156,281
Ending balance	154,697
Kurbo Health, Inc.
Goodwill [Line Items]
Beginning balance	156,281
Goodwill acquired during the period	1,101
Effect of exchange rate changes	(2,685)
Ending balance	154,697
Kurbo Health, Inc. \| North America
Goodwill [Line Items]
Beginning balance	140,389
Goodwill acquired during the period	1,101
Effect of exchange rate changes	(1,115)
Ending balance	140,375
Kurbo Health, Inc. \| Continental Europe
Goodwill [Line Items]
Beginning balance	7,759
Goodwill acquired during the period	0
Effect of exchange rate changes	(433)
Ending balance	7,326
Kurbo Health, Inc. \| United Kingdom
Goodwill [Line Items]
Beginning balance	1,253
Goodwill acquired during the period	0
Effect of exchange rate changes	(45)
Ending balance	1,208
Kurbo Health, Inc. \| Other
Goodwill [Line Items]
Beginning balance	6,880
Goodwill acquired during the period	0
Effect of exchange rate changes	(1,092)
Ending balance	$ 5,788

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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