Share-based compensation arrangement by share-based payment award, grant-date fair value.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Number Of Offering Periods

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Offering Period

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Purchase Period

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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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- Definition

Amount of cash inflow from issuance of shares under share-based payment arrangement. Excludes option exercised.

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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

Description of method used to estimate fair value of award under share-based payment arrangement.

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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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No definition available.

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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

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

+ References

No definition available.

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- Definition

Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ 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

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

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No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Employee Benefit Plans - Additional Information (Details) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
	Feb. 16, 2021 USD ($) $ / shares shares	Jun. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2021 USD ($) offering_period $ / shares shares	Jun. 30, 2020 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option granted \| shares				2,636,878
Exercise price \| $ / shares				$ 21.77
Allocated share-based compensation expense		$ 25,573	$ 19,471	$ 49,172	$ 36,973
Fair value assumptions, method used				Black-Scholes-Merton option pricing model
Aggregate proceeds from employee stock purchase plan				$ 3,873	3,082
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense		7,266	$ 6,087	14,108	$ 11,829
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option granted \| shares	580,911
Exercise price \| $ / shares	$ 21.99
Grant-date fair value of award	$ 5,700
Chief Executive Officer \| General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense		1,100		$ 1,600
2018 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period				24 months
Number of offering periods \| offering_period				4
Length of purchase period				6 months
Employee share purchase price percentage				85.00%
Modification charges under the reset provision		$ 2,000		$ 2,000
Time-Based Awards \| Equity Incentive Plans \| New Hires
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				4 years
Time-Based Awards \| Equity Incentive Plans \| Existing Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Maximum \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based payment award derived service period	3 years
Maximum \| Equity Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period				10 years
Minimum [Member] \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based payment award derived service period	9 months
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued under employee stock purchase plan, shares \| shares		246,000	268,000	246,000	268,000
Common Stock \| 2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant \| shares		17,129,162		17,129,162
Common Stock \| 2018 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued under employee stock purchase plan, shares \| shares		245,914	267,757	245,914	267,757
Weighted average purchase price \| $ / shares		$ 15.75	$ 11.51	$ 15.75	$ 11.51
Aggregate proceeds from employee stock purchase plan		$ 3,900	$ 3,100	$ 3,900	$ 3,100
Number of shares available for issuance \| shares		5,416,004		5,416,004