Stock-Based Incentive Compensation Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Performance Shares [Member]
Narrative [Abstract]
Vesting period (in years)	3 years
Performance Shares [Member] \| Maximum [Member]
Narrative [Abstract]
Share based compensation, Performance issuance as percent or original grant	200.00%
Performance Shares [Member] \| Minimum [Member]
Narrative [Abstract]
Share based compensation, Performance issuance as percent or original grant	0.00%
Stock options with performance conditions [Member]
Narrative [Abstract]
Contractual term	5 years
Vesting period (in years)	2 years
Total fair value of options vested	$ 1	$ 1	$ 2
Total intrinsic value of options exercised	$ 1	2	12
Stock options with service conditions [Member]
Narrative [Abstract]
Contractual term	10 years
Vesting period (in years)	3 years
Total fair value of options vested	$ 7	6	6
Total intrinsic value of options exercised	$ 3	11	23
SARs [Member]
Narrative [Abstract]
Contractual term	5 years
Vesting period (in years)	4 years
Percentage of SARs vesting each year over four-year period	25.00%
SARs liability	$ 1	1
Payment for SARs exercised	$ 1	$ 1	$ 3

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Percentage of vesting of share-based compensation awards.

+ References

No definition available.

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Share based compensation, Performance issuance as percent or original grant

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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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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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-Publisher FASB
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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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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