Stock Based Compensation - Stock Options, Restricted Stock and Restricted Stock Units Granted (Details)	9 Months Ended
Sep. 30, 2020 $ / shares shares
Stock Options:
Number of shares granted (shares)	8,000,000
Restricted Stock & RSU's:
Number of shares granted (shares)	501,259
Grant date fair value per share (USD per share) \| $ / shares	$ 25.87
Stock Options \| June 30, 2020 (1)
Stock Options:
Number of shares granted (shares)	4,160,000
Grant date fair value per share (USD per share) \| $ / shares	$ 4.80
Vesting period (in years)	0 years
Restricted Stock & RSU's:
Vesting period (in years)	0 years
Stock Options \| June 30, 2020 (2)
Stock Options:
Number of shares granted (shares)	3,840,000
Grant date fair value per share (USD per share) \| $ / shares	$ 5.19
Vesting period (in years)	3 years
Restricted Stock & RSU's:
Vesting period (in years)	3 years
Restricted Stock & RSU's \| August 12, 2020 (1)
Stock Options:
Vesting period (in years)	1 year
Restricted Stock & RSU's:
Number of shares granted (shares)	75,378
Grant date fair value per share (USD per share) \| $ / shares	$ 25.87
Vesting period (in years)	1 year
Restricted Stock & RSU's \| August 12, 2020 (2)
Stock Options:
Vesting period (in years)	2 years 9 months 18 days
Restricted Stock & RSU's:
Number of shares granted (shares)	220,335
Grant date fair value per share (USD per share) \| $ / shares	$ 25.87
Vesting period (in years)	2 years 9 months 18 days
Restricted Stock & RSU's \| August 12, 2020 (3)
Stock Options:
Vesting period (in years)	1 year 9 months 18 days
Restricted Stock & RSU's:
Number of shares granted (shares)	205,546
Grant date fair value per share (USD per share) \| $ / shares	$ 25.87
Vesting period (in years)	1 year 9 months 18 days

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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Gross number of share options (or share units) granted during the period.

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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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