Increase in common stock capital shares reserved for future issuance.

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Increase in number of shares reserved for issuance, percent of common stock outstanding.

+ References

No definition available.

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Aggregate number of common shares reserved for future issuance.

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- Definition

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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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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

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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.

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

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Stock-based Compensation Expense - Additional Information (Details) - USD ($)			1 Months Ended	12 Months Ended
	Jan. 01, 2020	Jul. 02, 2019	Jul. 31, 2016	Dec. 31, 2019	Dec. 31, 2018	Jul. 17, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense				$ 12,200,000
Unrecognized stock-based compensation expense, weighted average period expect to recognized				2 years 9 months 10 days
2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance		252,142
Increase in number of shares reserved for issuance (shares)		428,571
Increase in number of shares reserved for issuance, percent of common stock outstanding		1.00%
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance				2,023,828	507,891
Subsequent Event \| 2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of shares reserved for issuance (shares)	233,355
2016 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock that authorized for issuance					3,209,285
Shares reserved for future issuance				0		0
Shares issued			724,997
2016 Stock Incentive Plan \| Non-employee Founders and Certain Advisors \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued			65,713
2016 Stock Incentive Plan \| Non-employee Founders
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested in period			82,141
2016 Stock Incentive Plan \| Non-employee Founders \| Four Year Service Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
Vested in period			357,141
2016 Stock Incentive Plan \| Non-employee Founders \| One Year Service Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			1 year
Vested in period			285,715
2016 Stock Incentive Plan \| Non-employee Advisors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested in period			2,857
2016 Stock Incentive Plan \| Non-employee Advisors \| Four Year Service Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
Vested in period			34,285
2016 Stock Incentive Plan \| Non-employee Advisors \| Two Year Service Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			2 years
Vested in period			28,571
2019 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance		2,017,142		1,866,694
Increase in number of shares reserved for issuance (shares)		2,000,000
Increase in number of shares reserved for issuance, percent of common stock outstanding		4.00%
2019 Stock Incentive Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
2019 Stock Incentive Plan \| Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Contractual term				10 years
2019 Stock Incentive Plan \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of shares reserved for issuance (shares)	933,420
2019 Plan and 2016 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average grant date fair value				$ 6.97	$ 5.06
Aggregate intrinsic value of stock options exercised				$ 200,000	$ 0
2019 Plan and 2016 Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested in period				349,149	503,544
2019 Plan and 2016 Plan \| Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual term				9 years 1 month 13 days	9 years 10 months 2 days
Grants Outside of 2016 Stock Incentive Plan and 2019 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value of restricted stock awards vested				$ 4,800,000	$ 3,400,000
Grants Outside of 2016 Stock Incentive Plan and 2019 Stock Incentive Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested in period				112,142	112,143