Pension and Other Postretirement Benefit Plans - Summary of Changes in Fair Value of Company's Level 3 Pension Plan Assets (Details) - Pension Benefits - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	$ 788
Actual return on plan assets:
Fair value of plan assets December 31	700	$ 788
United States
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	9,804	9,094
Actual return on plan assets:
Fair value of plan assets December 31	9,717	9,804
United States \| Other
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	3
Actual return on plan assets:
Fair value of plan assets December 31	2	3
United States \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	3	4
Actual return on plan assets:
Relating to assets still held at December 31	(2)	(2)
Relating to assets sold during the year	2	2
Purchases and sales, net	(1)	(1)
Fair value of plan assets December 31	2	3
United States \| Level 3 \| Insurance Contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	0	0
Actual return on plan assets:
Relating to assets still held at December 31	0	0
Relating to assets sold during the year	0	0
Purchases and sales, net	0	0
Fair value of plan assets December 31	0	0
United States \| Level 3 \| Other
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	3	4
Actual return on plan assets:
Relating to assets still held at December 31	(2)	(2)
Relating to assets sold during the year	2	2
Purchases and sales, net	(1)	(1)
Fair value of plan assets December 31	2	3
International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	9,562	8,473
Actual return on plan assets:
Fair value of plan assets December 31	9,647	9,562
International \| Insurance Contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	788
Actual return on plan assets:
Fair value of plan assets December 31	701	788
International \| Other
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	4
Actual return on plan assets:
Fair value of plan assets December 31	0	4
International \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	785	761
Actual return on plan assets:
Relating to assets still held at December 31	(26)	77
Purchases and sales, net	(61)	(53)
Fair value of plan assets December 31	698	785
International \| Level 3 \| Insurance Contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	785	761
Actual return on plan assets:
Relating to assets still held at December 31	(26)	77
Purchases and sales, net	(61)	(53)
Fair value of plan assets December 31	698	785
International \| Level 3 \| Other
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	0	0
Actual return on plan assets:
Relating to assets still held at December 31	0	0
Purchases and sales, net	0	0
Fair value of plan assets December 31	$ 0	$ 0

No definition available.

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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 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.

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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.

+ References

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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/exampleRef
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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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