Retirement-Related Benefits - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2025 USD ($)
Pension Plan
Expected Benefit Payments
2026	$ 3,713
2027	3,635
2028	3,625
2029	3,608
2030	3,533
2031-2035	16,664
Other Postretirement Benefits Plan
Expected Benefit Payments
2026	312
2027	310
2028	305
2029	298
2030	290
2031-2035	1,291
United States \| Pension Plan \| Qualified Plan
Expected Benefit Payments
2026	1,180
2027	1,210
2028	1,224
2029	1,227
2030	1,187
2031-2035	5,587
United States \| Pension Plan \| Nonqualified Plan
Expected Benefit Payments
2026	119
2027	116
2028	114
2029	111
2030	108
2031-2035	489
United States \| Other Postretirement Benefits Plan
Expected Benefit Payments
2026	265
2027	262
2028	256
2029	248
2030	239
2031-2035	1,002
Non-U.S. Plans \| Pension Plan \| Qualified Plan
Expected Benefit Payments
2026	2,009
2027	1,938
2028	1,920
2029	1,906
2030	1,877
2031-2035	8,959
Non-U.S. Plans \| Pension Plan \| Nonqualified Plan
Expected Benefit Payments
2026	405
2027	371
2028	368
2029	363
2030	360
2031-2035	1,629
Non-U.S. Plans \| Other Postretirement Benefits Plan \| Qualified Plan
Expected Benefit Payments
2026	20
2027	21
2028	22
2029	23
2030	24
2031-2035	131
Non-U.S. Plans \| Other Postretirement Benefits Plan \| Nonqualified Plan
Expected Benefit Payments
2026	27
2027	27
2028	27
2029	27
2030	28
2031-2035	$ 158

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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 5
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: 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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- Definition

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 fourth 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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