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Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Modified, Weighted Average Grant Date Fair Value

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Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Granted Price

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Total Shareholder Return Based

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This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

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

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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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Amount of cost to be recognized for option under share-based payment arrangement.

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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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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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Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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Disclosure of the weighted average expected dividend for an entity using a valuation technique with different dividend rates during the contractual term.

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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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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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

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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 Payments - Narrative (Details) - USD ($)	1 Months Ended	12 Months Ended
Stock-based Payments - Narrative (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option life		3 years
Document Fiscal Year Focus		2019
Exercisable (USD per share)		$ 17.85
Pre-IPO stock-based compensation		$ 43,900,000	$ 63,400,000	$ 27,100,000
Time-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option life		0 years	6 years 4 months 24 days	5 years 6 months
Granted (in shares)		0	200,000	100,000
Fair value granted price (USD per share)			$ 6.13	$ 5.02
Exercisable (USD per share)		$ 0	$ 17.00	$ 17.00
Dividend yield		$ 0
Options modified (in shares)				1,300,000
Incremental expense				$ 3,700,000
Pre-IPO stock-based compensation		4,600,000	$ 6,000,000.0	$ 5,700,000
Unrecognized compensation cost related to non-vested time-based option awards		$ 1,000,000.0
Period compensation expense will be recognized		3 months 18 days
Weighted average exercise price per share, exercisable (USD per share)		$ 10.67
Performance-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option life			1 year 1 month 6 days	1 year 2 months 12 days
Granted (in shares)		0	100,000	100,000
Fair value granted price (USD per share)			$ 1.25	$ 2.23
Exercisable (USD per share)		$ 0	$ 17.00		$ 17.00
Pre-IPO stock-based compensation		$ 11,000,000.0	$ 1,400,000
Modified (USD per share)		$ 9.13		$ 11.06
Weighted average exercise price per share, exercisable (USD per share)		$ 0.00
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-IPO stock-based compensation		$ 45,700,000	64,700,000	$ 29,600,000
Restricted Stock Units (RSUs) \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting on annual AIP date		50.00%
Restricted Stock Units (RSUs) \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting on annual AIP date		50.00%
Performance-Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-IPO stock-based compensation		$ 1,900,000	$ 15,400,000	$ 0
Modified (USD per share)			$ 1.56
Granted (USD per share)		$ 19.64	3.18	$ 0
Margin accretion based	50.00%
Total shareholder return based (TSR)	50.00%
Time Based and Performance Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period		4 years
Granted (in shares)	1,800,000	400,000
Number of additional shares authorized	100,000
Dividend yield		$ 0
Minimum \| Performance-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option life		1 year
Minimum \| Time Based and Performance Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period		2 years
Weighted average exercise price per share, exercisable (USD per share)			2.00
Minimum \| Total Share Rewards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price per share, exercisable (USD per share)		$ 17.85
Maximum \| Time-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period		5 years
Maximum \| Performance-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option life		2 years
Maximum \| Time Based and Performance Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price per share, exercisable (USD per share)			$ 3.68
Maximum \| Total Share Rewards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price per share, exercisable (USD per share)		$ 21.43