XML 43 R30.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Nature of Operations and Significant Accounting Policies - Narrative (Details) mi in Thousands, $ in Millions | Jun. 30, 2018 state mi | Mar. 31, 2018 USD ($)
--- | --- | ---
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Total number of rail route miles | mi | 21 |
Number of states rail network serves | state | 23 |
Accumulated Other Comprehensive Income (Loss) |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification adjustment |  | $ (107)
Retained Earnings |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification adjustment |  | $ 107

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 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. + References No definition available. + Details
Name: | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems
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
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedOtherComprehensiveIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_RetainedEarningsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |