Summarized Consolidating Financial Data - Consolidating Income Statements (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Consolidated Income Statement
Revenue	$ 3,013	$ 2,876
Expense	1,794	1,832
Operating Income	1,219	1,044
Equity in Earnings of Subsidiaries	0	0
Interest (Expense) / Benefit	(178)	(149)
Other Income / (Expense) - Net	23	17
Earnings Before Income Taxes	1,064	912
Income Tax Benefit / (Expense)	(230)	(217)
Net Earnings	834	695
Total Comprehensive Earnings	836	596
Eliminations and Other
Consolidated Income Statement
Revenue	20	19
Expense	(37)	(33)
Operating Income	57	52
Equity in Earnings of Subsidiaries	(874)	(758)
Interest (Expense) / Benefit	49	24
Other Income / (Expense) - Net	(37)	(10)
Earnings Before Income Taxes	(805)	(692)
Income Tax Benefit / (Expense)	(16)	(12)
Net Earnings	(821)	(704)
Total Comprehensive Earnings	(819)	(700)
CSX Corporation
Consolidated Income Statement
Revenue	0	0
Expense	(137)	(78)
Operating Income	137	78
Equity in Earnings of Subsidiaries	874	758
Interest (Expense) / Benefit	(216)	(164)
Other Income / (Expense) - Net	8	4
Earnings Before Income Taxes	803	676
Income Tax Benefit / (Expense)	31	19
Net Earnings	834	695
Total Comprehensive Earnings	836	596
CSX Transportation
Consolidated Income Statement
Revenue	2,993	2,857
Expense	1,968	1,943
Operating Income	1,025	914
Equity in Earnings of Subsidiaries	0	0
Interest (Expense) / Benefit	(11)	(9)
Other Income / (Expense) - Net	52	23
Earnings Before Income Taxes	1,066	928
Income Tax Benefit / (Expense)	(245)	(224)
Net Earnings	821	704
Total Comprehensive Earnings	$ 819	$ 700