Stock-Based Compensation - Employee Stock Purchase Plan ("ESPP") - Additional Information (Detail) - Employee Stock Purchase Plan [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Rate of discount on fair market value of common stock under ESPP	15.00%
Company received proceeds	$ 0.8	$ 0.9
Period of expected life, options granted	5 years

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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