Retirement-Related Benefits - Contributions - (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Retirement-Related Benefits
Total plan contributions	$ 1,962	$ 2,085
Active Medical Trust
Retirement-Related Benefits
Contributions by employer - Noncash	557	424
Non-U.S. DB plans
Retirement-Related Benefits
Total plan contributions	103	86
Nonpension Postretirement Plans
Retirement-Related Benefits
Total plan contributions	344	319
Nonpension Postretirement Plans \| Non-U.S. DB plans
Retirement-Related Benefits
Contributions by employer - Noncash	349	$ 416
Non-US \| Pension Plans, Including Multi-employer Plans
Retirement-Related Benefits
Estimated cash contributions to the defined benefit plans in next fiscal year	$ 200

Noncash contributions made by the employer during the period to a defined benefit plan. These contributions may be in the form of securities.

No definition available.

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- Definition

Amount of contributions made by an employer to a defined benefit plan, defined contribution plan, or direct benefit payments.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921

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