Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	16,000,000
Number of shares available for grant (in shares)	3,600,000
Measurement period of specific annual performance goals, in years	1 year
Cliff vesting period following date of grant	2 years
Allocated share-based compensation expense	$ 38	$ 36	$ 32
Tax benefit from compensation expense	8	8	6
Compensation cost not yet recognized	$ 44
Compensation cost not yet recognized, period for recognition	1 year 9 months 18 days
Share-based compensation arrangement by share-based payment award, equity instruments other than options, vested in period, fair value	$ 34	$ 35	$ 36
Weighted average grant date fair value of awards granted (in usd per share)	$ 37.06	$ 46.78	$ 45.82
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	0.00%
Award vesting period	1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	200.00%
Award vesting period	3 years

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