Trade Accounts Receivable and Allowance for Doubtful Accounts - Summary of Trade Accounts Receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accounts Receivable Net Current [Abstract]
Trade accounts receivable	$ 3,903	$ 6,419
Allowance for doubtful accounts	(15)	(15)
Trade accounts receivable, net	3,888	6,404
Unpaid deferred revenue included in trade accounts receivable	$ 2,030	$ 2,217

Unpaid deferred revenues included in accounts receivable.

No definition available.

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
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-Section S99
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-Subparagraph (SX 210.7-03(5))
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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

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- References

No definition available.

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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