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Note 15 - Related Parties (Details Textual) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Accounts Payable, Current | $ 952 |  | $ 784
UPRR [Member] | TTX Company [Member] |  |  |
Accounts Payable, Current | 68 |  | 68
UPRR [Member] | TTX Company [Member] | Car Hire Expenses [Member] |  |  |
Other Expenses | $ 103 | $ 94 |
TTX Company [Member] | UPRR [Member] |  |  |
Equity Method Investment, Ownership Percentage | 37.03% |  |
Equity Method Investments | $ 1,700 |  | $ 1,700

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