Employee Benefit Plans (Amounts Recorded in Accumulated Other Comprehensive Income not yet Recognized) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension Benefits
Pension And Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
Balance, beginning of year	$ 3,126
Amortization for the period	160	$ 245	$ 262
Deferrals for the period	3,242	310
Impact of foreign currency changes and other	(221)	(174)
Balance, end of period	2,464	3,126
Pension Benefits | Prior Service Cost
Pension And Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
Balance, beginning of year	(5)	(10)	(12)
Amortization for the period	1	3	4
Deferrals for the period	1	0	0
Impact of foreign currency changes and other	1	2	(2)
Balance, end of period	(2)	(5)	(10)
Pension Benefits | Net Actuarial (Gain) Loss
Pension And Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
Balance, beginning of year	3,131	3,972	4,191
Amortization for the period	(160)	(245)	(262)
Deferrals for the period	(431)	(545)	42
Impact of foreign currency changes and other	(74)	(51)	1
Balance, end of period	2,466	3,131	3,972
Other Postretirement Benefits
Pension And Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
Balance, beginning of year	142
Amortization for the period	6	16	16
Deferrals for the period	364	55
Impact of foreign currency changes and other	(1)	(2)
Balance, end of period	168	142
Other Postretirement Benefits | Prior Service Cost
Pension And Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
Balance, beginning of year	(69)	59	65
Amortization for the period	8	(6)	(6)
Deferrals for the period	0	(121)	0
Impact of foreign currency changes and other	7	(1)	0
Balance, end of period	(54)	(69)	59
Other Postretirement Benefits | Net Actuarial (Gain) Loss
Pension And Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
Balance, beginning of year	211	354	341
Amortization for the period	(6)	(16)	(16)
Deferrals for the period	20	(127)	30
Impact of foreign currency changes and other	(3)	0	(1)
Balance, end of period	$ 222	$ 211	$ 354