Summary of Significant Accounting Policies - Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts receivable
Allowance for doubtful accounts	$ 0	$ 0
Trade accounts receivable	5,454	7,297
Unbilled accounts receivable	576	938
Allowance for product returns and price concessions	(231)	(713)
Accounts receivable, net	$ 5,799	$ 7,522

A valuation allowance for product returns and price concessions.

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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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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- References

No definition available.

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Period Type:	duration

- Definition

Amount of valuation allowance for receivables classified as other, due within one year or the normal operating cycle, if longer.

+ References

No definition available.

+ Details

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- Definition

Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

+ References

No definition available.

+ Details

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