Balance sheet components - Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 21,987	$ 19,350
Work in process	13,957	12,262
Finished goods	10,202	15,318
Inventories	46,146	46,930
Finished goods, at vendor managed inventory locations	$ 1,500	$ 1,600

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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Gross amount of merchandise or materials to which the entity holds the title, but physically at another entity's facilities (for example, but not limited to, work in process may be temporarily at the site of a subcontractor).

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