Summary of Impact of Accounts Receivable Reserves on Gross Trade Accounts Receivable Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross trade accounts receivable	$ 86,133	$ 57,802
Accounts receivable, net	66,523	45,318
Trade Allowances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Valuation allowances and reserves	(19,495)	(12,035)
Chargebacks
Accounts, Notes, Loans and Financing Receivable [Line Items]
Valuation allowances and reserves	$ (115)	$ (449)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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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.

+ References

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-Publisher FASB
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-SubTopic 10
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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.

+ 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)
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Amount of valuation and qualifying accounts and reserves.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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