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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

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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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02)(A) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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