Balance sheet components - Accounts receivable, net (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Accounts receivable	$ 57,471	$ 74,343
Trade notes receivable	2,409	672
Allowance for doubtful accounts	(257)	(264)
Account and trade note receivables, net	$ 59,623	$ 74,751

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	debit
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- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of allowance for credit loss on accounts receivable, classified as current.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount, before allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

+ References

No definition available.

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