Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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

Net number of non-option equity instruments granted to participants.

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- Definition

Percentage of vesting of share-based compensation awards.

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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 Compensation and Equity - Additional Information (Details) - USD ($) shares in Thousands, $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2018	Jul. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 48		$ 48
Unrecognized compensation expense, weighted average period			2 years 4 months 5 days
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)			85
Vesting period			3 years
Expiration term			10 years
Certain Employees \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	2	$ 17		$ 17	$ 21
Accelerated compensation cost	$ 7
Certain Employees \| Tranche One \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.30%
Certain Employees \| Tranche Two \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.30%
Certain Employees \| Tranche Three \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.40%