Accounts Receivable, Net - Summary of Accounts Receivable (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Receivables [Abstract]
Gross accounts receivable	$ 4,036	$ 4,036		$ 8,640
Allowance for uncollectible accounts	(1,684)	(1,684)		(80)
Total accounts receivable, net	2,352	2,352		$ 8,560
Provision for doubtful accounts	$ 1,600	$ 1,630	$ 0

For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

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-Publisher FASB
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- Definition

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

+ References

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No definition available.

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