Amount of performance units and restricted stock units settled in the year.

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

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Amount of tax benefit from exercise of 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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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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Number of shares authorized for issuance under share-based payment arrangement.

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Stock-Based Compensation (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	8.0
Maximum shares available for grants (in shares)	1.8
Settled performance share units and restricted stock units	$ 50	$ 58	$ 83
Compensation cost not yet recognized	$ 35
Expected weighted average recognition period for share-based compensation expense, in months	21 months
Income taxes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 5	$ 8	$ 15
Performance Share Units \| Market Condition PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Share-Based Compensation Arrangement By Share-Based Payment Award, Extended Award Vesting Period	38 months
Award Requisite Service Period	5 years
Percentage of shares issued per share unit, minimum	0.00%
Percentage of shares issued per share unit, maximum	200.00%
Stock Issued During Period Percentage Conversion Of Units, Mid-point	100.00%
Performance Share Units \| Performance Condition PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Share-Based Compensation Arrangement By Share-Based Payment Award, Extended Award Vesting Period	38 months
Award Requisite Service Period	5 years
Percentage of shares issued per share unit, minimum	0.00%
Percentage of shares issued per share unit, maximum	200.00%
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	38 months
Award Requisite Service Period	5 years