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Employee Benefits - Schedule of Fair Value of Other Plan Assets (Details) - Pension Plan - Other - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | $ 1,032 | $ 1,069 | $ 1,032
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 310 | 322 |
Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | (12) | (3) |
Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Cash and cash equivalents |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 18 | 26 |
Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 18 | 26 |
Cash and cash equivalents | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Cash and cash equivalents | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Equity securities |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 55 | 53 |
Equity securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 55 | 53 |
Equity securities | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Equity securities | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Equity investments, Pooled funds |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 208 | 204 |
Equity investments, Pooled funds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Equity investments, Pooled funds | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Equity investments, Pooled funds | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Government and agency bonds |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 237 | 243 |
Government and agency bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 237 | 243 |
Government and agency bonds | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Government and agency bonds | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Derivatives |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | (12) | (3) |
Derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Derivatives | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | (12) | (3) |
Derivatives | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 |  |
Fixed Income Investments, Pooled Funds |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 473 | 490 |
Fixed Income Investments, Pooled Funds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Fixed Income Investments, Pooled Funds | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Fixed Income Investments, Pooled Funds | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Alternative investments |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 47 | 47 |
Alternative investments | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Alternative investments | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Alternative investments | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Real estate |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 6 | 9 |
Real estate | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Real estate | Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | 0 | 0 |
Real estate | Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined benefit plan, plan assets | $ 0 | $ 0 |

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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 -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) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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