Number of carloads delivered

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Total number of ocean, river and lake ports that is served by the company.

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Number Of Primary Lines Of Business

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Number of Rail Labor Union Employees

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Number of short-line and regional railroads served by the company.

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Number Of Terminals

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Percentage of the total revenues.

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Percentage of the total volume.

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Rail Route Network, Distance

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Number of persons employed by the Entity

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Nature of Operations and Significant Accounting Policies (Details) mi in Thousands, carload in Thousands, unit in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($) employee railroad terminal state port_terminal mi	Dec. 31, 2025 employee railroad port_terminal state line_of_business terminal mi	Dec. 31, 2025 employee carload railroad state terminal port_terminal mi	Dec. 31, 2025 employee railroad terminal state port_terminal mi	Dec. 31, 2025 employee unit railroad port_terminal state terminal mi	Dec. 31, 2025 employee operatingSegment railroad state terminal port_terminal mi	Dec. 31, 2025 employee railroad port_terminal state terminal mi	Dec. 31, 2025 employee railroad port_terminal state segment terminal mi	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Revenue from External Customer [Line Items]
Number of rail route miles \| mi	20	20	20	20	20	20	20	20
Rail network states number \| state	26	26	26	26	26	26	26	26
Number of ocean, river and lake ports serviced (over) \| port_terminal	70	70	70	70	70	70	70	70
Number of short-line and regional railroads served (more than) \| railroad	250	250	250	250	250	250	250	250
Revenue	$ 14,092								$ 14,540	$ 14,657
Number of primary lines of business \| line_of_business		4
Number of operating segments						2		2
Number of employees (more than) \| employee	23,000	23,000	23,000	23,000	23,000	23,000	23,000	23,000
Number of rail labor union employees \| employee							16,900
Rail Operations
Revenue from External Customer [Line Items]
Number of operating segments \| operatingSegment						1
Merchandise business
Revenue from External Customer [Line Items]
Revenue	$ 8,773								8,903	8,653
Number of carloads \| carload			2,600
Percentage of total volume				41.00%
Percentage of total revenue				62.00%
Intermodal business
Revenue from External Customer [Line Items]
Revenue	$ 2,073								2,047	2,060
Number of carloads \| unit					3.0
Percentage of total volume				48.00%
Percentage of total revenue				15.00%
Number of terminals \| terminal	30	30	30	30	30	30	30	30
Coal business
Revenue from External Customer [Line Items]
Revenue	$ 1,900								2,247	2,484
Number of carloads \| carload			718
Percentage of total volume				11.00%
Percentage of total revenue				13.00%
Trucking business
Revenue from External Customer [Line Items]
Revenue	816								844	882
Percentage of total revenue				6.00%
Other
Revenue from External Customer [Line Items]
Revenue	$ 530								$ 499	$ 578
Percentage of total revenue				4.00%