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ACCUMULATED OTHER COMPREHENSIVE LOSS (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | $ 3 | $ 9 |  |
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 2 | 14 |  |
AOCI Tax, Attributable to Parent | 96 | 117 | $ 97 | $ 122
Accumulated Other Comprehensive Income (Loss), Net of Tax | (294) | (365) | (299) | (388)
Reclassification from AOCI, Current Period, Tax | (1) | (2) |  |
Income tax effect | 0 | (3) |  |
Marketable Securities |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
AOCI before Tax, Attributable to Parent | (45) | (78) | (46) | (104)
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent | 1 | 20 |  |
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent | 0 | 6 |  |
AOCI Employee Benefit Plan |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
AOCI before Tax, Attributable to Parent | (354) | (416) | (358) | (421)
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent | 0 | 0 |  |
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent | 4 | 5 |  |
AOCI - Interest Rate Derivatives |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
AOCI before Tax, Attributable to Parent | 9 | 12 | $ 8 | $ 15
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent | 1 | (3) |  |
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent | $ 0 | $ 0 |  |

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