Consideration Transferred (Parenthetical) (Detail) - USD ($) $ in Thousands		12 Months Ended
Apr. 01, 2016	Dec. 31, 2017
Business Acquisition [Line Items]
Working capital adjustment		$ 425
Atoll GmbH
Business Acquisition [Line Items]
Working capital adjustment	$ 74

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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