Retirement-Related Benefits - All Retirement Plans Cost (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Retirement-Related Benefits
Defined benefit and contribution pension plans - cost	$ 6,319	$ 598	$ 7,252	$ 1,816
Nonpension postretirement plans - cost	31	44	97	133
Total	$ 6,350	642	$ 7,350	1,949
Year-to-year percent change, nonpension postretirement plans cost (as a percent)	(30.20%)		(26.70%)
Pre-tax pension settlement charge	$ 5,900		$ 5,894
U.S. \| Pension Plans
Retirement-Related Benefits
Defined benefit and contribution pension plans - cost	6,012	$ 232	6,309	$ 694
Qualified Plans \| U.S. \| Pension Plans
Retirement-Related Benefits
Pre-tax pension settlement charge	$ 5,900		$ 5,900

The percentage change from year to year in the nonpension postretirement plans cost.

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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.

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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.

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No definition available.

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- Definition

Amount of cost (reversal of cost) for other postretirement benefits. Excludes pension benefits.

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No definition available.

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- Definition

Amount of cost (reversal of cost) for pension and other postretirement benefits.

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No definition available.

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- Definition

Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.

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No definition available.

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