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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No definition available.

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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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No definition available.

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- Definition

Percentage of the total volume.

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No definition available.

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- Definition

Rail Route Network, Distance

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- Definition

Shareholder Voting Percent

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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

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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- Definition

Amount of commitment made to pay deferred cash remuneration.

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- Definition

Amount of (increase) decrease in accumulated benefit obligation of defined benefit plan from effects of settlement and curtailment.

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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

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

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

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No definition available.

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- Definition

Expenditures for salaries of officers. Does not include allocated share-based compensation, pension and post-retirement benefit expense or other labor-related non-salary expense. For commercial and industrial companies, excludes any direct and overhead labor that is included in cost of goods sold.

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- Definition

The cash outflow to reacquire common stock during the period.

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- Definition

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

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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- Definition

Number of shares that have been repurchased and retired during the period.

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Nature of Operations and Significant Accounting Policies - Narrative (Details) mi in Thousands, carload in Thousands, shares in Millions, $ in Millions		1 Months Ended	3 Months Ended								12 Months Ended
	Jun. 05, 2017	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) employee railroad port_terminal state terminal mi	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 30, 2016 USD ($)	Sep. 23, 2016 USD ($)	Jun. 24, 2016 USD ($)	Mar. 25, 2016 USD ($)	Dec. 31, 2017 USD ($) employee railroad carload port_terminal state terminal mi shares	Dec. 30, 2016 USD ($) shares	Dec. 25, 2015 USD ($) shares
Revenue from External Customer [Line Items]
Number of employees \| employee			24,000								24,000
Number of union employees \| employee											20,000
Number of rail route miles \| mi			21								21
Rail network states number \| state			23								23
Number of short-line and regional railroads served \| railroad			230								230
Revenue			$ 2,863	$ 2,743	$ 2,933	$ 2,869	$ 3,037	$ 2,710	$ 2,704	$ 2,618	$ 11,408	$ 11,069	$ 11,811
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
Allowance for doubtful accounts			26				33				$ 26	33
Goodwill			63				$ 63				63	63
Pension and other post retirement benefit settlement charges											85
Shares acquired, repurchase amount											$ 1,970	$ 1,056	$ 804
Stock repurchased (in shares) \| shares											39	38	26
Shareholder vote percent	93.00%
Separation costs												$ 0	$ 51
Management streamlining
Revenue from External Customer [Line Items]
Workforce reduction (number of employees) \| employee											950
Chief Executive Officer
Revenue from External Customer [Line Items]
Reimbursement payment		$ 55
Lump sum cash payment			$ 29								$ 29
Minimum
Revenue from External Customer [Line Items]
Number of ocean, river and lake ports serviced (more than) \| port_terminal			70								70
Merchandise business
Revenue from External Customer [Line Items]
Number of carloads \| carload											2,700
Percentage of total revenue											62.00%
Percentage of total volume											42.00%
Coal business
Revenue from External Customer [Line Items]
Number of carloads \| carload											855
Percentage of total revenue											18.00%
Percentage of total volume											13.00%
Intermodal business
Revenue from External Customer [Line Items]
Percentage of total revenue											16.00%
Percentage of total volume											44.00%
Number of terminals (more than) \| terminal			40								40
Other business
Revenue from External Customer [Line Items]
Percentage of total revenue											4.00%