Stock-Based Compensation - (RSU) - Additional Information (Detail) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($) installment shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of vesting equal installments \| installment	36
Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of vesting equal installments \| installment	4
Unrecognized compensation expenses related to unvested RSUs \| $	$ 23.5
Unrecognized compensation expenses, weighted average period	1 year 9 months 18 days
Grant date fair value of common stock granted (in shares) \| shares	523,880
Grant date fair value of common stock vested \| $	$ 8.7

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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