Note 1 - Summary of Significant Accounting Policies - Changes in Carrying Amounts of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Balance	$ 68,754
Acquisitions	183,348
Purchase price accounting adjustments	1,377
Impairment	0	$ 0	$ 0
Foreign currency translation	(7,664)
Balance	$ 245,815	$ 68,754

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.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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