XML 123 R104.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Investment in Affiliates and Related-Party Transactions - Equity-method Investments in Affiliates (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Related Party Transaction [Line Items] |  |
Total | $ 2,099 | $ 1,985
Corporate Joint Venture | Conrail |  |
Related Party Transaction [Line Items] |  |
Total | 1,083 | 1,025
Affiliated Entity |  |
Related Party Transaction [Line Items] |  |
Total | 2,099 | 1,985
Affiliated Entity | TTX |  |
Related Party Transaction [Line Items] |  |
Total | 849 | 796
Affiliated Entity | Other |  |
Related Party Transaction [Line Items] |  |
Total | $ 167 | $ 164

X
- Definition Amount of investment in equity method investee and investment in and advance to affiliate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_RelatedPartyTransactionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_CorporateJointVentureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=csx_ConrailMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=csx_TTXCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=csx_OherEquityMethodInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |