Retirement-Related Benefits - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2023 USD ($)
Pension Plan
Expected Benefit Payments
2024	$ 4,260
2025	4,286
2026	4,283
2027	4,225
2028	4,145
2029-2033	19,591
Other Postretirement Benefits Plan
Expected Benefit Payments
2024	261
2025	260
2026	259
2027	255
2028	281
2029-2033	1,349
United States \| Pension Plan \| Qualified Plan
Expected Benefit Payments
2024	1,769
2025	1,830
2026	1,848
2027	1,822
2028	1,780
2029-2033	8,284
United States \| Pension Plan \| Nonqualified Plan
Expected Benefit Payments
2024	122
2025	121
2026	119
2027	116
2028	113
2029-2033	522
United States \| Other Postretirement Benefits Plan
Expected Benefit Payments
2024	217
2025	215
2026	213
2027	208
2028	233
2029-2033	1,085
Non-U.S. Plans \| Pension Plan \| Qualified Plan
Expected Benefit Payments
2024	1,995
2025	1,977
2026	1,954
2027	1,933
2028	1,903
2029-2033	9,131
Non-U.S. Plans \| Pension Plan \| Nonqualified Plan
Expected Benefit Payments
2024	375
2025	359
2026	362
2027	354
2028	349
2029-2033	1,654
Non-U.S. Plans \| Other Postretirement Benefits Plan \| Qualified Plan
Expected Benefit Payments
2024	20
2025	21
2026	22
2027	23
2028	24
2029-2033	134
Non-U.S. Plans \| Other Postretirement Benefits Plan \| Nonqualified Plan
Expected Benefit Payments
2024	24
2025	24
2026	24
2027	24
2028	24
2029-2033	$ 129

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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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