Related Party and Party-In Interest Transactions (Details) - EBP 004 $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($)
EBP, Nonconsolidated, Master Trust
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Interest income on investment	$ 652
CSX Common Stock \| EBP, Nonconsolidated, Master Trust
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Dividend income on investment	13,200
CSX Common Stock \| EBP, Nonconsolidated, Plan Interest in Master Trust
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Dividend income on investment	$ 8,700

Amount of increase in net asset available for benefit from interest income on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Excludes interest income on note receivable from participant.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477783/962-325-50-7

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477063/962-205-45-7

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(1)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Name:	us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestIncomeOnInvestment
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration