Represents the maximum number of common shares that could be issued upon vesting of outstanding awards.

No definition available.

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- Definition

The total fair value of shares issued during the period under a deferred compensation arrangement.

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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.

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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

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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- Definition

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).

+ References

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- Definition

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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

+ References

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- References

No definition available.

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- Definition

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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- Definition

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

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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

Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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- Definition

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

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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SHARE-BASED COMPENSATION - RSUs (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
RSUs
Share-based compensation
Percentage of vesting rights	33.00%
Vesting period	3 years
Time-Based RSUs
Share-based compensation
Remaining unrecognized compensation expense related to non-vested awards	$ 55
Total fair value	$ 66	$ 34	$ 30
Weighted-average remaining requisite service period over which unrecognized compensation cost is expected to be amortized	1 year 6 months
RSUs
Beginning of the period (in shares)	6,100,000
Granted (in shares)	3,300,000
Vested (in shares)	(3,400,000)
Forfeited (in shares)	(300,000)
End of the period (in shares)	5,700,000	6,100,000
Weighted- Average Grant-Date Fair Value Per Share
Beginning of the period (in dollars per share)	$ 20.54
Granted (in dollars per share)	21.92
Vested (in dollars per share)	19.37
Forfeited (in dollars per share)	21.78
End of the period (in dollars per share)	$ 21.98	$ 20.54
Performance-Based Restricted Stock Units
Share-based compensation
Remaining unrecognized compensation expense related to non-vested awards	$ 22
Weighted-average remaining requisite service period over which unrecognized compensation cost is expected to be amortized	1 year 4 months 24 days
Maximum common shares issuable upon vesting (in shares)	3,729,000
RSUs
Beginning of the period (in shares)	2,000,000.0
Granted (in shares)	897,000
Vested (in shares)	(600,000)
End of the period (in shares)	2,300,000	2,000,000.0
Weighted- Average Grant-Date Fair Value Per Share
Beginning of the period (in dollars per share)	$ 25.80
Granted (in dollars per share)	26.61
Vested (in dollars per share)	19.02
End of the period (in dollars per share)	$ 28.10	$ 25.80
Method and assumptions on valuation of stock options
Contractual term (years)	3 years	3 years	3 years
Expected Company share volatility	38.60%	46.50%	54.20%
Risk-free interest rate	1.20%	2.50%	2.70%
Performance-Based Restricted Stock Units \| Chief Executive Officer
Share-based compensation
Aggregate value of long term incentive awards			$ 10
Number of shares canceled (in shares)			933,000
TSR Performance-Based Restricted Stock Units
RSUs
Granted (in shares)	425,000
Weighted- Average Grant-Date Fair Value Per Share
Granted (in dollars per share)	$ 26.13
ROTC Performance-Based Restricted Stock Units
RSUs
Granted (in shares)	472,000
Weighted- Average Grant-Date Fair Value Per Share
Granted (in dollars per share)	$ 27.05