v3.25.4

Pension and other postretirement benefits - Level 3 Rollforward (Details) - Pension Plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets, beginning of year	$ 0	$ 0
Fair value of plan assets, end of year	0	0
Non-U.S.
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets, beginning of year	175	669
Fair value of plan assets, end of year	246	175
Non-U.S. | Equity instruments
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets, beginning of year	28
Fair value of plan assets, end of year	56	28
Non-U.S. | Insurance contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets, beginning of year	93
Fair value of plan assets, end of year	90	93
Non-U.S. | Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets, beginning of year	95	494
Actual return on plan assets, relating to assets still held at reporting date	1	23
Purchases, sales and settlements	(8)	(402)
Change due to exchange rate changes	4	(20)
Fair value of plan assets, end of year	92	95
Non-U.S. | Level 3 | Equity instruments
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets, beginning of year	2	26
Actual return on plan assets, relating to assets still held at reporting date	0	0
Purchases, sales and settlements	0	(24)
Change due to exchange rate changes	0	0
Fair value of plan assets, end of year	2	2
Non-U.S. | Level 3 | Insurance contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets, beginning of year	93	468
Actual return on plan assets, relating to assets still held at reporting date	1	23
Purchases, sales and settlements	(8)	(378)
Change due to exchange rate changes	4	(20)
Fair value of plan assets, end of year	$ 90	$ 93

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- Definition

Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) For Foreign Exchange Rate

+ References

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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.

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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.

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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.

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