Accumulated Other Comprehensive Income (Loss) - Reclassifications out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Revenue	$ 106,116	$ 131,174	$ 247,594	$ 342,760
Cost of revenue	95,613	101,427	225,496	255,666
Research and development	16,701	16,100	52,456	41,929
Sales and marketing	13,657	12,843	42,389	37,123
General and administrative	11,062	$ 8,357	32,512	$ 19,553
Foreign currency contracts
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	100		257
Gain (losses) on cash flow hedge \| Foreign currency contracts
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Revenue	100		257
Cost of revenue	0		0
Research and development	0		0
Sales and marketing	0		0
General and administrative	0		0
Amount Reclassified from AOCI \| Foreign currency contracts
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	78		258
Amount Reclassified from AOCI \| Gain (losses) on cash flow hedge \| Foreign currency contracts
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Revenue	86		333
Cost of revenue	0		(2)
Research and development	(3)		(24)
Sales and marketing	(3)		(38)
General and administrative	$ (2)		$ (11)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Amount before tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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