Retirement-Related Benefits - Level 3 Reconciliation (Details) - Level 3 - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
United States \| Personal Pension Plan (PPP)
Change in plan assets
Fair value of plan assets, balance at beginning of period	$ 722	$ 1,142
Return on assets held at end of year	2	(23)
Return on assets sold during the year	16	10
Purchases, sales and settlements, net	(554)	(409)
Transfers, net	6	2
Fair value of plan assets, balance at end of period	193	722
United States \| Personal Pension Plan (PPP) \| Equity Securities
Change in plan assets
Fair value of plan assets, balance at beginning of period	0
Return on assets held at end of year	(2)
Return on assets sold during the year	0
Purchases, sales and settlements, net	2
Transfers, net	7
Fair value of plan assets, balance at end of period	7	0
United States \| Personal Pension Plan (PPP) \| Corporate Bonds
Change in plan assets
Fair value of plan assets, balance at beginning of period	709	721
Return on assets held at end of year	4	(18)
Return on assets sold during the year	16	10
Purchases, sales and settlements, net	(545)	(5)
Transfers, net	1	2
Fair value of plan assets, balance at end of period	186	709
United States \| Personal Pension Plan (PPP) \| Private Equity
Change in plan assets
Fair value of plan assets, balance at beginning of period	13	421
Return on assets held at end of year	0	(5)
Return on assets sold during the year	0	0
Purchases, sales and settlements, net	(10)	(404)
Transfers, net	(2)	0
Fair value of plan assets, balance at end of period	0	13
Non-U.S. Plans
Change in plan assets
Fair value of plan assets, balance at beginning of period	78	155
Return on assets held at end of year	0	(65)
Return on assets sold during the year	5	56
Purchases, sales and settlements, net	(77)	(74)
Transfers, net	0	0
Foreign exchange impact	(4)	7
Fair value of plan assets, balance at end of period	3	78
Non-U.S. Plans \| Fixed income mutual funds
Change in plan assets
Fair value of plan assets, balance at beginning of period	75	9
Return on assets held at end of year	0	1
Return on assets sold during the year	5	0
Purchases, sales and settlements, net	(77)	63
Transfers, net	0	0
Foreign exchange impact	(3)	2
Fair value of plan assets, balance at end of period	0	75
Non-U.S. Plans \| Real estate
Change in plan assets
Fair value of plan assets, balance at beginning of period	4	145
Return on assets held at end of year	0	(66)
Return on assets sold during the year	0	56
Purchases, sales and settlements, net	0	(137)
Transfers, net	0	0
Foreign exchange impact	(1)	5
Fair value of plan assets, balance at end of period	$ 3	$ 4

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets sold.

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

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- Definition

Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.

+ References

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Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan, for assets transferred into (out of) Level 3 of fair value hierarchy. Includes, but is not limited to, transfer due to change in observability of significant inputs.

+ References

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