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PENSIONS AND OTHER POSTRETIREMENT BENEFITS - Narrative (Details) | Jan. 01, 2023 USD ($) | Dec. 31, 2022 USD ($) | Nov. 01, 2022 USD ($) | Oct. 31, 2022 USD ($) | Oct. 12, 2022 location employee | Sep. 30, 2022 USD ($) employee
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Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Term of labor agreement |  |  |  |  | 4 years | 47 months
Number of employees covered by labor agreement | employee |  |  |  |  | 12,000 | 2,000
Number of locations covered by labor agreement | location |  |  |  |  | 13 |
Service multiplier |  |  |  |  |  | $ 115
Contribution per eligible hour |  |  | $ 4.00 | $ 0.50 |  |
Forecast |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Service multiplier | $ 126 |  |  |  |  |
Fixed income | Pension Benefits |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Plan asset investment |  | $ 1,200,000,000 |  |  |  |
Externally Managed Assets | Pension Benefits |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Plan asset investment |  | $ 2,900,000,000 |  |  |  |

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- Definition Amount of investment within defined benefit plan asset category. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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