Balance sheet components - Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Accounts receivable	$ 61,914	$ 68,988
Trade notes receivable	0	156
Allowance for doubtful accounts	(251)	(254)
Account and trade note receivables, net	$ 61,663	$ 68,890

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
-Name Accounting Standards Codification
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- Definition

Amount of allowance for credit loss on accounts receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References

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- Definition

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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