Accrued unvested common stock subject to repurchase current.

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- Definition

Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock.

+ References

No definition available.

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- Definition

Maximum shares allowed to be issued.

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- Definition

Maximum shares allowed to be issued under ESPP.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award purchase price of common stock through payroll deductions percentage.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award stock offering period.

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- Definition

Unvested common shares subject to repurchase outstanding.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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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- Definition

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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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

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Stock Option Plan - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Jan. 01, 2019	Sep. 01, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Jul. 31, 2017	Feb. 28, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation				$ 2,623	$ 256
Total intrinsic value of options exercised				$ 1,800
Weighted-average grant date fair value per share for options granted				$ 10.41	$ 2.78
Stock option exercised				89,050	0
Remaining shares subject to repurchase				151,289	265,098
Liability for unvested common shares subject to repurchase included in accrued expenses and other liabilities				$ 112	$ 123
2015 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issue						3,225,346	2,446,323
Stock option vesting period				4 years
Stock options expiration period				10 years
Number of shares available for future grant				0
2018 Incentive Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issue			3,186,205
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock			4.00%
Maximum shares of common stock may be issued			20,887,347
Number of shares outstanding available for future grant				1,896,926
2018 Incentive Award Plan \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock	4.00%
Number of additional shares added to the plan	1,494,341
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issue			353,980
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock			1.00%
Maximum shares allowed to be issued under ESPP			4,778,738
Purchase of common stock through payroll deductions expressed in percentage of fair market value		85.00%		85.00%
Common stock offering period		6 months
Stock-based compensation				$ 100
Employee Stock Purchase Plan \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock	1.00%
Number of additional shares added to the plan	373,585
2015 and 2018 Stock Incentive Plans
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense				$ 15,700
Unrecognized compensation expense estimated to be recognized over period				2 years 10 months 24 days