XML 74 R56.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Stock Plans and Share-Based Compensation - Restricted Stock Grant and Vesting Information (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Weighted-average grant date fair value (in dollars per share) | $ 62.60 | $ 48.35 | $ 24.21
Fair value of units vested in fiscal year ending (in millions) | $ 9 | $ 8 | $ 14

X
- Definition Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options Weighted Average Grant Date Fair Value + References No definition available. + Details
Name: | csx_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsWeightedAverageGrantDateFairValue
Namespace Prefix: | csx_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |