Share-based compensation arrangement by share-based payment award options vested.

No definition available.

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- Definition

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

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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- Definition

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

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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.

+ References

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- Definition

Amount of tax benefit from exercise of option under share-based payment arrangement.

+ References

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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- Definition

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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- 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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

+ References

No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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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- Definition

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

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Share-Based Compensation - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Oct. 01, 2018	Sep. 12, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized common stock (in shares)	135,000,000			250,000,000
Award performance period	1 year
Restriction period for restricted common stock	3 years
Total Intrinsic value of options exercised	$ 1,000,000	$ 1,000,000	$ 6,000,000
Total fair value of shares vested	$ 0	0	2,000,000
Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restriction period for restricted common stock	3 years
Unrecognized compensation expense	$ 40,000,000
Unrecognized compensation expense period	2 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted shares vested	$ 8,000,000	11,000,000	14,000,000
LTPU and RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restriction period for restricted common stock	3 years
LTPU and RSU \| Performance Targets, Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
LTPU and RSU \| Market Targets, Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
Cash Settled Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 3,000,000	(1,000,000)	4,000,000
Share-Settled RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	19,000,000	11,000,000	11,000,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	0
Cash received from stock option exercises	1,000,000	1,000,000	8,000,000
Tax benefit from exercise of stock options	$ 1,000,000	$ 1,000,000	$ 2,000,000
2006 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized common stock (in shares)					3,000,000.0
Shares of common stock remain authorized for delivery (in shares)	1,964,372
2006 Long-Term Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock remain authorized for delivery (in shares)	14,800,000