Reversal Of Stock Based Compensation Expense

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- Definition

Reversal Of Stock Based Compensation Previously Recognized

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Tranches

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-Section S99
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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

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 were forfeited during the reporting period.

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-Publisher FASB
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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

Percentage of vesting of award under share-based payment arrangement.

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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

Weighted average grant-date fair value of non-vested options outstanding.

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No definition available.

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Stockholders' Equity - Co-Founder Grants (Details) $ / shares in Units, shares in Millions, $ in Millions		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 19, 2020 USD ($) shares	Dec. 31, 2017 USD ($) tranche $ / shares shares	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($)	Dec. 31, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share) \| $ / shares			$ 5.69		$ 5.69
Reversal of stock based compensation expense \| $	$ 23.8
Reversal Of Stock Based Compensation Previously Recognized \| $	$ 21.5
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)					22.5
Shares forfeited (in shares)					7.6
Co-Founder Grants \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		14.7					14.7
Expiration period		10 years
Number of tranches \| tranche		9
Weighted average grant date fair value (in dollars per share) \| $ / shares		$ 10.60
Unamortized stock-based compensation, requisite service period		5 years 2 months 12 days
Remaining unamortized stock-based compensation \| $		$ 156.2	$ 40.6		$ 40.6
Shares forfeited (in shares)	4.4
Stock-based compensation related to the Co-Founder Grants \| $			$ 6.2	$ 8.8	$ 18.4	$ 26.1
Co-Founder Grants \| Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation, requisite service period		2 years 10 months 24 days
Co-Founder Grants \| Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation, requisite service period		6 years 10 months 24 days
Co-Founder Grants \| Restricted Stock \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Co-Founder Grants \| Restricted Stock \| Tranche One \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vested maximum		20.00%
Co-Founder Grants \| Chief Executive Officer \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		10.3			10.3
Co-Founder Grants \| Director \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		4.4
Shares forfeited (in shares)	4.4