Debt and Credit Agreements (Details) (USD $)	3 Months Ended		3 Months Ended
	Mar. 30, 2012	Feb. 29, 2012 Notes Payable 4.4% Notes Due 2043	Mar. 30, 2012 Current Liabilities	Mar. 30, 2012 Long Term Liabilities
Movement, Debt Instruments [Roll Forward]
Current Portion	$ 507,000,000		$ 507,000,000
Long-term Portion	8,734,000,000			8,734,000,000
Long-term Debt	9,241,000,000
Long-term debt issued	300,000,000		0	300,000,000
Long-term debt repaid	(413,000,000)		(413,000,000)	0
Reclassifications	0		(408,000,000)	408,000,000
Debt conversions to CSX stock	0		0	0
Discount and premium activity	(3,000,000)		0	(3,000,000)
Current Portion	502,000,000		502,000,000
Long-term Debt Portion	8,623,000,000			8,623,000,000
Long-term Debt	9,125,000,000
Notes issued, face amount		300,000,000
Notes issued, interest rate		4.40%
Employer contribution to qualified pension plans	$ 275,000,000