The increase (decrease) during the reporting period in the aggregate amount of expenses incurred.

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Share-based Payment Arrangement, Total Equity Grant to Employees, Number of Employees

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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

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Aggregate number of common shares reserved for future issuance.

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

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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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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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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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

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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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Expected term of 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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Stock-Based Compensation - Narrative (Details) $ / shares in Units, employee in Thousands, shares in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2020 USD ($) employee	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares	May 31, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized		$ 51,300,000	$ 19,200,000	$ 2,800,000
Risk-free interest rate (as a percent)		2.00%
Expected dividend rate (as a percent)		0.00%
Accrued liabilities		$ 787,100,000	$ 244,100,000
Weighted average grant date fair value of stock options granted (USD per share) \| $ / shares		$ 9.29	$ 10.16	$ 13.67
Share-based Payment Arrangement, Total Equity Grant to Employees	$ 150,000,000
Share-based Payment Arrangement, Total Equity Grant to Employees, Number of Employees \| employee	16
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Expected life of options (in years)		2 years 9 months 25 days
Risk-free interest rate (as a percent)		0.50%
Volatility rate (as a percent)		35.20%
Expected dividend rate (as a percent)		0.00%
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized				$ (8,200,000)
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of stock options exercised		$ 66,000,000.0	$ 109,800,000	20,800,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
2013 Stock Incentive Plan and 2017 Omnibus Incentive Plan \| Former Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized		2,900,000	1,000,000.0
2013 Stock Incentive Plan and 2017 Omnibus Incentive Plan \| Equity Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized		47,100,000	10,200,000
2013 Stock Incentive Plan and 2017 Omnibus Incentive Plan \| Equity Awards - Founders Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized	$ 19,000,000.0
2013 Stock Incentive Plan and 2017 Omnibus Incentive Plan \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase (decrease) in liabilities		$ 1,300,000	8,000,000.0
Omnibus Incentive Plan 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized				7,200,000
Omnibus Incentive Plan 2017 \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period		10 years
2013 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capital stock reserved for future issuance (shares) \| shares		20.9
Stock-based compensation expense recognized				3,800,000
2013 Stock Incentive Plan \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accrued liabilities		$ 3,500,000	$ 7,800,000
2013 Stock Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized				$ 2,800,000
Unrecognized compensation expense		166,900,000
2013 Stock Incentive Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense		$ 166,900,000
2013 Stock Incentive Plan \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rate (as a percent)		50.00%
2013 Stock Incentive Plan \| Tranche One \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rate (as a percent)		50.00%
2013 Stock Incentive Plan \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rate (as a percent)		50.00%
2013 Stock Incentive Plan \| Tranche Two \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rate (as a percent)		50.00%
2013 Stock Incentive Plan \| Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rate (as a percent)		50.00%
2013 Stock Incentive Plan \| Tranche Three \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rate (as a percent)		50.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)		1 year
Volatility rate (as a percent)		26.80%
Minimum \| Omnibus Incentive Plan 2017 \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		4 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)		1 year 3 months 18 days
Volatility rate (as a percent)		27.30%
Maximum \| Omnibus Incentive Plan 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capital stock reserved for future issuance (shares) \| shares					19.6
Maximum \| Omnibus Incentive Plan 2017 \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		5 years