Selected Balance Sheet Components - Schedule of inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Inventory:
Raw materials	$ 9,265	$ 6,085
Work-in-process	771	541
Finished goods	44	190
Inventory	$ 10,080	$ 6,816

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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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.

+ References

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

+ References

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-Publisher FASB
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-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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