Comprehensive Income (Reclassification Out Of AOCI) (Details) - Reclassification Out Of Accumulated Other Comprehensive Income [Member] - OPEB [Member] - Amortization Of Defined Benefit Cost Items [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, pretax	$ 5	$ 3
Tax impact	(1)
Reclassifications, net of tax	$ 4	$ 3