XML 56 R42.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Nature of Operations and Significant Accounting Policies (Business) (Details) mi in Thousands, employees in Thousands, carloads in Millions, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 25, 2015 USD ($) employees terminals railroads state port_terminals mi | Sep. 25, 2015 USD ($) | Jun. 26, 2015 USD ($) | Mar. 27, 2015 USD ($) | Dec. 26, 2014 USD ($) | Sep. 26, 2014 USD ($) | Jun. 27, 2014 USD ($) | Mar. 28, 2014 USD ($) | Dec. 25, 2015 USD ($) employees terminals railroads state carloads port_terminals mi | Dec. 26, 2014 USD ($) | Dec. 27, 2013 USD ($)
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of employees | employees | 29 |  |  |  |  |  |  |  | 29 |  |
Number of union employees | employees |  |  |  |  |  |  |  |  | 24 |  |
Number of rail route miles | mi | 21 |  |  |  |  |  |  |  | 21 |  |
Rail network states number | state | 23 |  |  |  |  |  |  |  | 23 |  |
Number of short-line and regional railroads served | railroads | 240 |  |  |  |  |  |  |  | 240 |  |
Revenue | $ | $ 2,781 | $ 2,939 | $ 3,064 | $ 3,027 | $ 3,192 | $ 3,221 | $ 3,244 | $ 3,012 | $ 11,811 | $ 12,669 | $ 12,026
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of ocean, river and lake ports serviced (more than) | port_terminals | 70 |  |  |  |  |  |  |  | 70 |  |
Merchandise business [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of carloads | carloads |  |  |  |  |  |  |  |  | 2.9 |  |
Percentage of total revenue |  |  |  |  |  |  |  |  | 62.00% |  |
Percentage of total volume |  |  |  |  |  |  |  |  | 42.00% |  |
Coal business [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of carloads | carloads |  |  |  |  |  |  |  |  | 1.1 |  |
Percentage of total revenue |  |  |  |  |  |  |  |  | 19.00% |  |
Percentage of total volume |  |  |  |  |  |  |  |  | 16.00% |  |
Intermodal business [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percentage of total revenue |  |  |  |  |  |  |  |  | 15.00% |  |
Percentage of total volume |  |  |  |  |  |  |  |  | 42.00% |  |
Number of terminals (more than) | terminals | 50 |  |  |  |  |  |  |  | 50 |  |
Other business [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percentage of total revenue |  |  |  |  |  |  |  |  | 4.00% |  |

X
- Definition Minimum number of terminals. + References No definition available. + Details
Name: | csx_MinimumNumberOfTerminals
Namespace Prefix: | csx_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of carloads delivered + References No definition available. + Details
Name: | csx_NumberOfCarloads
Namespace Prefix: | csx_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total number of ocean, river and lake ports that is served by the company. + References No definition available. + Details
Name: | csx_NumberOfOceanRiverAndLakePortsServiced
Namespace Prefix: | csx_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of short-line and regional railroads served by the company. + References No definition available. + Details
Name: | csx_NumberOfShortLineAndRegionalRailroadsServed
Namespace Prefix: | csx_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of Union Employees + References No definition available. + Details
Name: | csx_NumberOfUnionEmployees
Namespace Prefix: | csx_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of the total revenues. + References No definition available. + Details
Name: | csx_PercentageOfTotalRevenue
Namespace Prefix: | csx_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of the total volume. + References No definition available. + Details
Name: | csx_PercentageOfTotalVolume
Namespace Prefix: | csx_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Rail Route Network, Distance + References No definition available. + Details
Name: | csx_RailRouteNetworkDistance
Namespace Prefix: | csx_
Data Type: | num:lengthItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of persons employed by the Entity + References No definition available. + Details
Name: | dei_EntityNumberOfEmployees
Namespace Prefix: | dei_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- 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. + References No definition available. + Details
Name: | us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of states the entity operates in as of the balance sheet date. + References No definition available. + Details
Name: | us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
Name: | us-gaap_SalesRevenueNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=csx_MerchandiseBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=csx_CoalBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=csx_IntermodalBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=csx_OtherBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |