Revenue Recognition - Summary of Receivables and Contract Liabilities From Contracts with Customers (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Change In Contract With Customer Liability [Abstract]
Accounts receivable, gross	$ 20,252	$ 12,263
Chargebacks and other deductions	(13,154)	(3,711)
Allowance for doubtful accounts	(27)	(84)
Accounts receivable, net	7,071	8,468
Deferred revenue	364	1,202
Total contract liabilities	$ 364	$ 1,202

Chargebacks and other deductions current.

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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.

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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.

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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.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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