Increase to amount of stock available under plan, total number of shares of common stock outstanding, percentage.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Nonvested, Grant Date Fair Value

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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

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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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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

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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- 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

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

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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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SHARE-BASED AWARDS - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 18, 2020	Feb. 06, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised, aggregate intrinsic value		$ 46,200	$ 9,700	$ 39,200
Options granted		$ 0.00	$ 1.50	$ 1.50
Stock-based compensation expense		$ 38,005	$ 13,196	$ 14,974
2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized						106,320,623
2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	43,508,048	43,508,048
Total number of shares of common stock outstanding on December 31 of the immediately preceding calendar year	5.00%	5.00%
Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period		10 years
Vesting period		4 years
Incentive stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period		5 years
Employee Stock Purchase Plan \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized					54,385,060
Common stock reserved for issuance					5,438,506
Total number of shares of common stock outstanding on December 31 of the immediately preceding calendar year	1.00%	1.00%
RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period		7 years
Vesting period		4 years
Unamortized stock-based compensation costs	$ 503,000	$ 503,000
RSU \| Time-based vesting condition \| Public Offering And Over-Allotment Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation costs	80,200	$ 80,200
Options that have fully satisfied the time-based vesting condition (in shares)		9,201,201
Vesting of restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested options, aggregate intrinsic value		$ 8,900	$ 1,500	$ 100
Options that have fully satisfied the time-based vesting condition (in shares)		1,339,000
Vesting of restricted shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Vesting of restricted shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Market Condition Award \| Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value for awards	$ 357,400	$ 357,400
Stock-based compensation expense		$ 19,900
Market Condition Award \| Executive Officer \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period	6 months
Market Condition Award \| Executive Officer \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period		3 years 6 months
Unvested stock options and Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation costs	$ 13,500	$ 13,500
Unamortized stock-based compensation period (in years)		1 year 9 months 18 days