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, 2023	Dec. 31, 2022
Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	$ 765
Actual return on plan assets:
Fair value of plan assets December 31	788	$ 765
United States
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	9,094	13,067
Actual return on plan assets:
Fair value of plan assets December 31	9,804	9,094
United States \| 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	3	4
United States \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	4	6
Actual return on plan assets:
Relating to assets still held at December 31	(2)	(3)
Relating to assets sold during the year	2	2
Purchases and sales, net	(1)	(1)
Fair value of plan assets December 31	3	4
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	4	6
Actual return on plan assets:
Relating to assets still held at December 31	(2)	(3)
Relating to assets sold during the year	2	2
Purchases and sales, net	(1)	(1)
Fair value of plan assets December 31	3	4
International
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	8,473	12,195
Actual return on plan assets:
Fair value of plan assets December 31	9,562	8,473
International \| Insurance Contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	780
Actual return on plan assets:
Fair value of plan assets December 31	788	780
International \| Other
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	2
Actual return on plan assets:
Fair value of plan assets December 31	4	2
International \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	761	937
Actual return on plan assets:
Relating to assets still held at December 31	77	(147)
Purchases and sales, net	(53)	(39)
Transfers into Level 3	0	10
Fair value of plan assets December 31	785	761
International \| Level 3 \| Insurance Contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets January 1	761	937
Actual return on plan assets:
Relating to assets still held at December 31	77	(147)
Purchases and sales, net	(53)	(39)
Transfers into Level 3	0	10
Fair value of plan assets December 31	785	761
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
Transfers into Level 3	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 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 715
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Reference 6: http://www.xbrl.org/2003/role/exampleRef
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
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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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- Definition

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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