Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		9 Months Ended
Apr. 15, 2019	Sep. 30, 2020
Unrecognized compensation cost related to unvested employee and director stock-based awards		$ 6.5
Weighted average period for unrecognized compensation cost		2 years 8 months 12 days
2019 Stock Plan [Member]
Shares available for future issuance	3,428,571	2,465,687
2019 Stock Plan [Member] \| Common Stock [Member] \| Service Based Vesting [Member]
Options granted		585,336
Options granted weighted average grant fair value of per share		$ 7.95
2019 Stock Plan [Member] \| Maximum [Member]
Number of shares underlying awards increase (decrease)	1,595,189
2014 Stock Incentive Plan [Member] \| Maximum [Member]
Number of shares underlying awards forfeited in period	1,595,189
2019 Employee Stock Purchase Plan [Member]
Shares available for future issuance	371,142
Shares available for future issuance, Grant		348,445
Number of share issued		22,697

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Number of shares authorized for issuance under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Other than shares newly issued, the number of additional shares issued (for example, a stock split) or canceled (for example, to correct a share issuance), during the period under the plan.

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Number of shares issued under share-based payment arrangement.

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