Summarized Consolidating Financial Data - Consolidating Income Statement (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 27, 2015	Mar. 28, 2014
Consolidated Income Statement
Revenue	$ 3,027us-gaap_SalesRevenueNet	$ 3,012us-gaap_SalesRevenueNet
Expense	2,184us-gaap_CostsAndExpenses	2,273us-gaap_CostsAndExpenses
Operating Income	843us-gaap_OperatingIncomeLoss	739us-gaap_OperatingIncomeLoss
Equity in Earnings of Subsidiaries	0	0
Interest (Expense) / Benefit	(134)us-gaap_InterestExpense	(140)us-gaap_InterestExpense
Other Income / (Expense) - Net	2us-gaap_OtherNonoperatingIncomeExpense	7us-gaap_OtherNonoperatingIncomeExpense
Earnings Before Income Taxes	711	606
Income Tax Benefit / (Expense)	(269)us-gaap_IncomeTaxExpenseBenefit	(208)us-gaap_IncomeTaxExpenseBenefit
Net Earnings	442us-gaap_NetIncomeLoss	398us-gaap_NetIncomeLoss
Total Comprehensive Earnings	440us-gaap_ComprehensiveIncomeNetOfTax	414us-gaap_ComprehensiveIncomeNetOfTax
CSX Corporation
Consolidated Income Statement
Revenue	0	0
Expense	(148)	(103)
Operating Income	148	103
Equity in Earnings of Subsidiaries	440	416
Interest (Expense) / Benefit	(133)	(130)
Other Income / (Expense) - Net	(1)	(2)
Earnings Before Income Taxes	454	387
Income Tax Benefit / (Expense)	(12)	11
Net Earnings	442	398
Total Comprehensive Earnings	440	414
CSX Transportation
Consolidated Income Statement
Revenue	3,007	2,992
Expense	2,344	2,393
Operating Income	663	599
Equity in Earnings of Subsidiaries	0	0
Interest (Expense) / Benefit	(7)	(14)
Other Income / (Expense) - Net	6	6
Earnings Before Income Taxes	662	591
Income Tax Benefit / (Expense)	(246)	(204)
Net Earnings	416	387
Total Comprehensive Earnings	413	393
Eliminations and Other
Consolidated Income Statement
Revenue	20	20
Expense	(12)	(17)
Operating Income	32	37
Equity in Earnings of Subsidiaries	(440)	(416)
Interest (Expense) / Benefit	6	4
Other Income / (Expense) - Net	(3)	3
Earnings Before Income Taxes	(405)	(372)
Income Tax Benefit / (Expense)	(11)	(15)
Net Earnings	(416)	(387)
Total Comprehensive Earnings	$ (413)	$ (393)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Total costs of sales and operating expenses for the period.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The net result for the period of deducting operating expenses from operating revenues.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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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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