Employee Benefit Plans (Schedule of Defined Benefit Plan Disclosures) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Other	$ (51)	$ 65	$ 23
Fair value of plan assets	48,945	47,960
Noncurrent liability	(2,385)	(4,807)
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	49,592	49,028	67,214
Service cost	222	470	523
Interest cost	2,507	1,520	1,249
Actuarial loss (gain)	1,909	(15,466)
Total benefits paid (1)	(4,258)	(4,328)
Net settlement, curtailment, and special termination benefits	5	3
Plan amendments	19	131
Other	160	(516)
Fair value of plan assets	48,945	47,960	63,323
Actual return on plan assets	4,730	(10,841)
Employer contributions (1)	363	306
Total benefits paid (1)	(4,258)	(4,328)
Settlements	(2)	(4)
Other (2)	152	(496)
Funded status of plan	(647)	(1,068)
Noncurrent assets	1,296	3,301
Current liability	(206)	(236)
Noncurrent liability	(1,737)	(4,133)
Net amount recognized	(647)	(1,068)
Net actuarial loss (gain)	4,311	2,950
Prior service credit	(1,246)	(1,424)
Net amount recognized	3,065	1,526
Pension Plan [Member] | Continuing operations [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	222	470
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	962	984	1,370
Service cost	3	6	7
Interest cost	50	29	24
Actuarial loss (gain)	53	(294)
Total benefits paid (1)	(176)	(166)
Net settlement, curtailment, and special termination benefits	(9)	(8)
Plan amendments	0	0
Other	57	47
Fair value of plan assets	316	302	$ 389
Actual return on plan assets	37	(63)
Employer contributions (1)	106	98
Total benefits paid (1)	(176)	(166)
Settlements	(9)	(8)
Other (2)	56	52
Funded status of plan	(646)	(682)
Noncurrent assets	0	0
Current liability	(64)	(71)
Noncurrent liability	(582)	(611)
Net amount recognized	(646)	(682)
Net actuarial loss (gain)	(325)	(394)
Prior service credit	(3)	(4)
Net amount recognized	(328)	(398)
Other Postretirement Benefits Plan [Member] | Continuing operations [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3	$ 6