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Benefit Plans (Schedule of Amounts Recognized in Other Comprehensive Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Amounts arising during the period	$ 50	$ (12)	$ 262
Settlement	0	0	1
Reclassification adjustment relating to prior service credit	0	0	0
Reclassification adjustment relating to actuarial loss	34	30	46
Total increase (decrease) in Other comprehensive income	$ 84	$ 18	$ 309

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Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Settlements, before Tax

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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