Pension and Other Postretirement Benefit Plans - Fair Values of Pension Plan Assets (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 700	$ 788
United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9,717	9,804	$ 9,094
United States | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	164	158
United States | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,555	2,797
United States | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,265	740
United States | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	174	113
United States | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,171	2,071
United States | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,101	2,307
United States | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,293	1,485
United States | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	21
United States | Derivatives
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(29)	109
United States | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	3
United States | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,355	2,438
United States | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	43	34
United States | Level 1 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	170	224
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	2,171	2,071
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	(29)	109
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	3,415	3,813
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	2,101	2,307
United States | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,293	1,485
United States | Level 2 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	21
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	2	3	4
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	2	3	4
United States | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,945	3,550
United States | NAV | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	121	124
United States | NAV | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,385	2,573
United States | NAV | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,265	740
United States | NAV | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	174	113
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	9,647	9,562	8,473
International | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	123	118
International | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,232	3,870
International | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	145	110
International | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	10
International | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,385	3,523
International | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	180	197
International | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	19	20
International | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	287	278
International | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	368	423
International | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	141	160
International | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54	61
International | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	701	788
International | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	4
International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,345	1,197
International | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	112	98
International | Level 1 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	599	507
International | Level 1 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54	44
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	262	234
International | Level 1 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23	23
International | Level 1 | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	9
International | Level 1 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	287	278
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	0	4
International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,090	7,041
International | Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 2 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,537	3,257
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	0
International | Level 2 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,974	3,123
International | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	8
International | Level 2 | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	8
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	368	423
International | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	141	160
International | Level 2 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54	61
International | Level 2 | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
International | Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	698	785	761
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	698	785	761
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	514	539
International | NAV | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11	20
International | NAV | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	96	106
International | NAV | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	91	66
International | NAV | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	10
International | NAV | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	149	166
International | NAV | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	149	166
International | NAV | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	3
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	2
International | NAV | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0