Condensed consolidated financial statement details - Product Warranty (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Beginning balances	$ 7,452,000	$ 8,954,000	$ 8,523,000	$ 11,398,000
Charged to cost of revenue	4,114,000	1,269,000	6,769,000	2,986,000
Settlements of warranty claims	(3,945,000)	(2,897,000)	(7,671,000)	(7,058,000)
Ending balances	7,621,000	$ 7,326,000	7,621,000	$ 7,326,000
Warranty liability	7,234,000		7,234,000		$ 7,997,000
Product Warranty Accrual, Noncurrent	$ 400,000		$ 400,000		$ 500,000

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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.

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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).

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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.

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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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