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Pension and Other Postretirement Benefit Plans - Fair Values of Pension Plan Assets (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 943	$ 942
United States
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,067	12,672	$ 11,361
United States | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	292	308
United States | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,035	4,090
United States | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	919	1,096
United States | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	89
United States | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,915	2,819
United States | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,870	2,236
United States | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,005	1,994
United States | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23	33
United States | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	7
United States | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,156	3,199
United States | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	5
United States | Level 1 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	236	206
United States | Level 1 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	169
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 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,915	2,819
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 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	0
United States | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,898	4,352
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 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	89
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	2,870	2,236
United States | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,005	1,994
United States | Level 2 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23	33
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	6	7	9
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 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States | Level 3 | Real estate, Investment funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	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 | 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	6	7	9
United States | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,007	5,114
United States | NAV | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	289	303
United States | NAV | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,799	3,884
United States | NAV | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	919	927
United States | NAV | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
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 | 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	12,195	12,009	10,135
International | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	110	131
International | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,944	4,879
International | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	209	246
International | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,436	4,302
International | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	188	189
International | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	26	24
International | Real estate, Investment funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17	16
International | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	369	505
International | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	597	487
International | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	225	177
International | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	90	70
International | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	982	978
International | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	5
International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,387	2,779
International | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	82	110
International | Level 1 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	531	475
International | Level 1 | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	137	154
International | Level 1 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	240	1,516
International | Level 1 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9	5
International | Level 1 | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	9
International | Level 1 | Real estate, Investment funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International | Level 1 | Developed markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	369	505
International | Level 1 | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	3
International | Level 1 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1
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	1	1
International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9,293	7,696
International | Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	1
International | Level 2 | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,292	4,286
International | Level 2 | Emerging markets equities
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	4,025	2,614
International | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	12
International | Level 2 | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	11
International | Level 2 | Real estate, Investment funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
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	591	481
International | Level 2 | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	223	174
International | Level 2 | Mortgage and asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	90	70
International | Level 2 | Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	44	42
International | Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	4
International | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	937	935	851
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 | 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 | Real estate, Investment funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	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	937	935	851
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	578	599
International | NAV | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18	20
International | NAV | Developed markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	121	118
International | NAV | Emerging markets equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	72	92
International | NAV | Government and agency obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	171	172
International | NAV | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	171	172
International | NAV | Other fixed income obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	4
International | NAV | Real estate, Investment funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	16	15
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	3	3
International | NAV | Corporate obligations
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2
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	1	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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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