Organization and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) customer	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]
Number of customers \| customer	2
Percentage of revenue	10.00%
Percentage of accounts receivable	10.00%
Sales returns coverage period	30 days
Unbilled accounts receivable	$ 4.7		$ 5.1
Deferred revenue recognized	$ 2.4	$ 1.5
Amortization period for incentive compensation costs	1 year
Distributor A
Organization And Summary Of Significant Accounting Policies [Line Items]
Percentage of revenue	15.00%	13.00%
Percentage of accounts receivable	17.00%		19.00%
Distributor B
Organization And Summary Of Significant Accounting Policies [Line Items]
Percentage of revenue	11.00%	14.00%
Percentage of accounts receivable	11.00%		15.00%

Amortization Period for Incentive Compensation Costs

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Concentration Risk, Percentage of Accounts Receivable attributable to customer

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Customer Concentration, Number Of Customers

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Organization And Summary Of Significant Accounting Policies [Line Items]

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Revenue Recognition, Sales Returns, Coverage Period

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Unbilled amounts due for 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 entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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