Share Based Compensation Arrangement By Share Based Payment Award Award Cliff Vesting Period.

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- Definition

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

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

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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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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 share-based payment arrangement.

+ References

No definition available.

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- Definition

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

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

+ References

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- Definition

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

+ References

No definition available.

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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

Expected term of 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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Stock-based Compensation - 2017 Equity Incentive Plan (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Jan. 01, 2020	Jan. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2021
Stock-based Compensation
Stock options total intrinsic value of stock options					$ 7,980
Nonemployees
Stock-based compensation
Expected term (in years)			10 years
2017 Equity Incentive Plan
Stock-based Compensation
Common stock reserved for issuance	1,759,870	1,376,429	5,375,772			1,769,436
Percentage increase in authorized shares under the plan			4.00%
Stock options total intrinsic value of stock options			$ 2,661	$ 3,844
Authorized shares			7,484,536
Shares available for future grant			2,108,764
Common stock reserved for issuance	1,759,870	1,376,429	5,375,772			1,769,436
Grant cliff vesting period			1 year
Number of common stock options granted			2,546,075	1,445,200	1,218,790
Weighted average grant date fair value relating to outstanding stock options			$ 13.25	$ 17.19	$ 17.27
2017 Equity Incentive Plan \| Exercise Price Not Less Than 100% Of Fair Market Value
Stock-based Compensation
Exercise price of incentive stock options over fair market value of the common stock			100.00%
2017 Equity Incentive Plan \| Exercise Price Not Less Than 110% Of Fair Market Value
Stock-based Compensation
Exercise price of incentive stock options over fair market value of the common stock			110.00%
2017 Equity Incentive Plan \| Employees
Stock-based compensation
Risk-free interest rate			0.76%	2.40%	2.73%
Expected term (in years)			6 years 29 days	6 years 25 days	5 years 10 months 20 days
Expected volatility			70.67%	66.03%	62.21%
2017 Employee Stock Purchase Plan
Stock-based Compensation
Common stock reserved for issuance			1,000,993
Number of additional shares added	439,968	344,107
Percentage increase in authorized shares under the plan			1.00%
Common stock reserved for issuance			1,000,993
Number of common stock options granted			30,052
Maximum \| 2017 Equity Incentive Plan
Stock-based Compensation
Vesting period of stock option awards			4 years
Maximum \| 2017 Equity Incentive Plan \| Exercise Price Not Less Than 110% Of Fair Market Value
Stock-based Compensation
Voting power of stock			10.00%
Minimum \| 2017 Equity Incentive Plan
Stock-based Compensation
Vesting period of stock option awards			1 year
Minimum \| 2017 Equity Incentive Plan \| Exercise Price Not Less Than 100% Of Fair Market Value
Stock-based Compensation
Voting power of stock			10.00%