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

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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

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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-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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.

+ References

No definition available.

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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

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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-Publisher FASB
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- Definition

Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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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 non-vested options outstanding.

+ References

No definition available.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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Equity Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions		9 Months Ended
	Feb. 06, 2019	Sep. 30, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding awarded (in shares)		10,266,895	8,538,060
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs		$ 20.7
Weighted-average period of cost expects to recognize		2 years 2 months 12 days
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield		0.00%
Aggregate intrinsic value, options vested in period		$ 0.7
Weighted-average grant date fair value (in dollars per share)		$ 10.61
Aggregate fair value of stock options vested during period		$ 23.1
Stock-Based Compensation Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period of cost expects to recognize		2 years 6 months
Unrecognized compensation expense related to the ESPP.		$ 61.3
2019 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share reserved for future issuance	5,750,000
Term of awards	10 years
Percentage of amount increase in outstanding shares	5.00%
Common stock available for issuance (in shares)		1,696,802
Shares outstanding awarded (in shares)		7,291,966
2019 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share reserved for future issuance	700,000
Term of awards	10 years
Percentage of amount increase in outstanding shares	1.00%
Number of share issued under ESPP		113,286
Number of share reserved for future issuance		1,249,554
2019 Employee Stock Purchase Plan \| Stock-Based Compensation Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period of cost expects to recognize		1 year
Unrecognized compensation expense related to the ESPP.		$ 1.9
2019 Employee Stock Purchase Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of common stock through payroll deductions, percentage	20.00%
2017 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding awarded (in shares)		4,071,312
2017 Equity Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted (in shares)		342,006