Employee Benefit Plans (Net Periodic Benefit Costs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pension Benefits
Net periodic benefit costs [Abstract]
Service costs	$ 41	$ 38	$ 122	$ 113
Interest costs	114	118	342	353
Expected return on plan assets	(115)	(119)	(345)	(360)
Amortization of net actuarial (gains) losses	42	40	125	118
Amortization of prior service costs (credit)	(3)	(3)	(9)	(9)
Net periodic benefit costs (credit)	79	74	235	215
Other Postretirement Benefits
Net periodic benefit costs [Abstract]
Service costs	0	1	2	2
Interest costs	10	11	30	32
Expected return on plan assets	(14)	(13)	(42)	(41)
Amortization of net actuarial (gains) losses	(7)	(7)	(21)	(22)
Amortization of prior service costs (credit)	0	0	0	0
Net periodic benefit costs (credit)	$ (11)	$ (8)	$ (31)	$ (29)