Condensed consolidated financial statement details - Product Warranty (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Beginning balances	$ 11,945	$ 10,856	$ 6,405
Charged to cost of revenue	20,139	19,272	25,377
Settlements of warranty claims	(21,711)	(18,183)	(20,926)
Ending balances	10,373	11,945	$ 10,856
Product Warranty Accrual, Current	9,934	$ 11,456
Product Warranty Accrual, Noncurrent	$ 400

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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-Publisher FASB
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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

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The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

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