Retirement-Related Benefits - Pension and Nonpension Postretirement Plan Changes (Details) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) item	Sep. 30, 2022 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Retirement-Related Benefits
Benefit plan obligation and plan assets transferred to insurers		$ 16,000
Pre-tax pension settlement charge		5,900	$ 5,894
Pension settlement charge, net of tax		4,400
Accumulated other comprehensive income/(loss)	$ (17,138)	$ (17,138)	$ (17,138)	$ (23,234)
Qualified Plans \| Pension Plans \| U.S.
Retirement-Related Benefits
Benefit plan obligation and plan assets transferred to insurers	$ 16,000
Number of participants transferred to insurers \| item	100,000
Percentage of transferred participant pension benefits each insurer is responsible to pay	50.00%	50.00%	50.00%
Pre-tax pension settlement charge		$ 5,900	$ 5,900
Pension settlement charge, net of tax		4,400
Accumulated benefit obligation	$ 21,316	$ 21,316	$ 21,316

Amount of benefit plan obligation and related plan assets transferred to insurers.

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- Definition

Percentage of pension benefits for participants transferred that each insurer is responsible to pay.

+ References

No definition available.

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Number of participants transferred to insurers.

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- Definition

Non-cash, pre-tax pension settlement charges relating to accelerated recognition of accumulated actuarial losses resulting from irrevocable transfer of defined benefit pension obligations and related plan assets under group annuity contracts.

+ References

No definition available.

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Non-cash, pension settlement charges relating to accelerated recognition of accumulated actuarial losses resulting from irrevocable transfer of defined benefit pension obligations and related plan assets under group annuity contracts, net of tax.

+ References

No definition available.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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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.

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