Cash Equivalents, Maximum Maturity Period

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- Definition

Percentage ownership in companies indicating not majority owned and with no significant influence where such ownership in the companies are reported using the cost method otherwise equity method.

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- Definition

Minimum number of terminals.

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- Definition

Number of carloads delivered

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- Definition

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

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- Definition

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

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- Definition

Number of Union Employees

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- Definition

Percentage of the total revenues.

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- Definition

Percentage of the total volume.

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- Definition

Rail Route Network, Distance

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- Definition

Short-term Investments, Maximum Maturity Period

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- Definition

Short-term Investments, Minimum Maturity Period

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- Definition

Number of persons employed by the Entity

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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- Definition

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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- Definition

The number of states the entity operates in as of the balance sheet date.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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- Definition

The number of positions eliminated during the period as a result of restructuring activities.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Nature of Operations and Significant Accounting Policies - Narrative (Details) carload in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018 USD ($) employee railroad port_terminal state terminal mi	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) employee railroad carload port_terminal state terminal mi	Dec. 31, 2017 USD ($) employee	Dec. 30, 2016 USD ($)	Jan. 01, 2019 USD ($)
Revenue from External Customer [Line Items]
Number of rail route miles \| mi	20,500								20,500
Rail network states number \| state	23								23
Number of short-line and regional railroads served \| railroad	230								230
Revenue	$ 3,143	$ 3,129	$ 3,102	$ 2,876	$ 2,863	$ 2,743	$ 2,933	$ 2,869	$ 12,250	$ 11,408	$ 11,069
Number of employees \| employee	22,500								22,500
Number of union employees \| employee									18,500
Cost method, maximum percentage									20.00%
Cash equivalents maximum maturity period (in months)									3 months
Short-term investments, minimum maturity period									3 months
Short-term investments, maximum maturity period									1 year
Scenario, Forecast \| Accounting Standards Update 2016-02
Revenue from External Customer [Line Items]
Right-of-use assets												$ 650
Lease liabilities												$ 625
Management streamlining
Revenue from External Customer [Line Items]
Workforce reduction \| employee										950
Minimum
Revenue from External Customer [Line Items]
Number of ocean, river and lake ports serviced (more than) \| port_terminal	70								70
Accumulated Other Comprehensive Income (Loss)
Revenue from External Customer [Line Items]
Cumulative effect of new accounting pronouncement				(107)
Retained Earnings
Revenue from External Customer [Line Items]
Cumulative effect of new accounting pronouncement				$ 107
Merchandise business
Revenue from External Customer [Line Items]
Number of carloads \| carload									2,700
Percentage of total volume									41.00%
Percentage of total revenue									61.00%
Coal business
Revenue from External Customer [Line Items]
Number of carloads \| carload									887
Percentage of total volume									14.00%
Percentage of total revenue									18.00%
Intermodal business
Revenue from External Customer [Line Items]
Number of carloads \| carload									2,900
Percentage of total volume									45.00%
Percentage of total revenue									16.00%
Number of terminals (more than) \| terminal	30								30
Other business
Revenue from External Customer [Line Items]
Percentage of total revenue									5.00%