Summary of Components of Accounts Receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Receivables Net Current [Abstract]
Product sales, net of discounts and allowances	$ 90,409	$ 48,252
Government contract receivables	470	792
Total accounts receivable, net	$ 90,879	$ 49,044

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.

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- Definition

Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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- Definition

The amount of receivables that are derived from government contracts.

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No definition available.

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