Summary of Significant Accounting Policies (Details)	12 Months Ended
Dec. 31, 2019 commodity_group CubicYard / mi NumberOfDepreciableAssetClass ties / ft ft
Finite-Lived Intangible Assets [Line Items]
Number of commodity groups \| commodity_group	7
Property, Plant and Equipment [Abstract]
Rail and related track material, minimum level of activity to be capitalized \| ft	39
Ties installation, minimum level of activity to be capitalized \| ties / ft	5
Ballast installation, minimum level of activity to be capitalized \| CubicYard / mi	171
Number of depreciable asset classes \| NumberOfDepreciableAssetClass	40
Intangible Assets
Intangible assets amortization method	straight-line basis
Pensions
Pension Plan amortization of cumulative net actuarial gains and losses excess threshold	10.00%
Postretirement benefits amortization of cumulative net actuarial gains and losses excess threshold	10.00%
Minimum [Member]
Leases
Renewal term	1 year
Intangible Assets
Intangible asset useful life	20 years
Maximum [Member]
Leases
Renewal term	5 years
Intangible Assets
Intangible asset useful life	50 years

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Number Of Commodity Groups

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Pension Plan's amortization of cumulative net actuarial gains and losses percentage in excess of, the greater of the beginning of year balances of the projected benefit obligation or market-related value of plan assets, over the expected average remaining service life of the employee group covered by the plans.

+ References

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Other postretirement benefits amortization of cumulative net actuarial gains and losses percentage in excess of the projected benefit obligation at the beginning of the year, over the expected average remaining service life of the employee group covered by the plan.

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Describes the minimum level of activity of costs an entity capitalizes as part of property, plant and equipment, including the costs incurred for repairs and maintenance activities.

+ References

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Describes the minimum level of activity of costs an entity capitalizes as part of property, plant and equipment, including the costs incurred for repairs and maintenance activities.

+ References

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Describes the minimum level of activity of costs an entity capitalizes as part of property, plant and equipment, including the costs incurred for repairs and maintenance activities.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amortization method of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company. The straight-line method is the preferred amortization method, unless another method better reflects the pattern in which the asset is consumed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 35
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=108376495&loc=d3e15372-109273

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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