Note 17 - Related Parties (Details Textual) - UPRR [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
TTX Company [Member]
Accounts Payable, Related Parties, Current	$ 65		$ 65		$ 57
TTX Company [Member] \| Car Hire Expenses [Member]
Related Party Transaction, Expenses from Transactions with Related Party	$ 98	$ 95	$ 192	$ 191
TTX Company [Member]
Equity Method Investment, Ownership Percentage	36.79%		36.79%
Equity Method Investments	$ 1,600		$ 1,600		$ 1,600

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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