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PENSIONS AND OTHER POSTRETIREMENT BENEFITS - Narrative (Details) - Pension Benefits - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Fixed income |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Plan asset investment |  | $ 1,200
Externally Managed Assets |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Plan asset investment |  | $ 2,900
Private equity |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Reserve for investment commitments | $ 70 |

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- Definition Amount of investment within defined benefit plan asset category. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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 + Details
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