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Pension and Other Postretirement Benefit Plans - Fair Values of Pension Plan Assets (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 788	$ 765
United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9,804	9,094	$ 13,067
United States | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	158	147
United States | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,797	2,654
United States | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	740	707
United States | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	113	131
United States | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,071	1,956
United States | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,307	2,047
United States | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,485	1,438
United States | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	22
United States | Derivatives
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	109	(12)
United States | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	4
United States | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,438	2,193
United States | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	34	38
United States | Level 1 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	224	211
United States | Level 1 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 1 | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 1 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,071	1,956
United States | Level 1 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 1 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 1 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 1 | Derivatives
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	109	(12)
United States | Level 1 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,813	3,507
United States | Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 2 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 2 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 2 | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 2 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 2 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,307	2,047
United States | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,485	1,438
United States | Level 2 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	22
United States | Level 2 | Derivatives
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	4	6
United States | Level 3 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Derivatives
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
United States | Level 3 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	4	6
United States | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,550	3,390
United States | NAV | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	124	109
United States | NAV | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,573	2,443
United States | NAV | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	740	707
United States | NAV | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	113	131
United States | NAV | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | NAV | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | NAV | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | NAV | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | NAV | Derivatives
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | NAV | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9,562	8,473	12,195
International | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	118	78
International | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,870	3,422
International | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	110	111
International | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	11
International | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,523	2,963
International | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	197	146
International | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20	21
International | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	278	263
International | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	423	450
International | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	160	157
International | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	61	69
International | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	788	780
International | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	2
International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,197	943
International | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	98	57
International | Level 1 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	507	375
International | Level 1 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	44	52
International | Level 1 | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 1 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	234	177
International | Level 1 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23	8
International | Level 1 | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9	10
International | Level 1 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	278	263
International | Level 1 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 1 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 1 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 1 | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 1 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	1
International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,041	6,333
International | Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	8
International | Level 2 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,257	2,957
International | Level 2 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 2 | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1
International | Level 2 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,123	2,656
International | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	9
International | Level 2 | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	7
International | Level 2 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 2 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	423	450
International | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	160	157
International | Level 2 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	61	69
International | Level 2 | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	18
International | Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1
International | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	785	761	937
International | Level 3 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3 | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	785	761	937
International | Level 3 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	$ 0
International | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	539	436
International | NAV | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20	13
International | NAV | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106	90
International | NAV | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	66	59
International | NAV | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	10
International | NAV | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	166	130
International | NAV | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	166	129
International | NAV | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	4
International | NAV | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | NAV | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | NAV | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | NAV | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | NAV | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	1
International | NAV | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

X

- Definition

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+ References

No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
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