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Note 14 - Commitments and Contingencies (Tables) | 9 Months Ended
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Sep. 30, 2023
Notes Tables |
Schedule of Loss Contingencies by Contingency, Environmental [Table Text Block] |
Millions, for the Nine Months Ended September 30, |  | 2023 |  |  | 2022 |
Beginning balance |  | $ | 253 |  |  | $ | 243 |
Accruals |  |  | 85 |  |  |  | 65 |
Payments |  |  | (75 | ) |  |  | (45 | )
Ending balance at September 30, |  | $ | 263 |  |  | $ | 263 |
Current portion, ending balance at September 30, |  | $ | 83 |  |  | $ | 64 |
Personal Injury [Member] |
Notes Tables |
Schedule of Loss Contingencies by Contingency [Table Text Block] |
Millions, for the Nine Months Ended September 30, |  | 2023 |  |  | 2022 |
Beginning balance |  | $ | 361 |  |  | $ | 325 |
Current year accruals |  |  | 81 |  |  |  | 79 |
Changes in estimates for prior years |  |  | 55 |  |  |  | 36 |
Payments |  |  | (104 | ) |  |  | (93 | )
Ending balance at September 30, |  | $ | 393 |  |  | $ | 347 |
Current portion, ending balance at September 30, |  | $ | 105 |  |  | $ | 77 |

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