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

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. 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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- Definition

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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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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- Definition

Amount of expense classified as other.

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