Debt and Credit Agreements (Debt Issuance) (Details) (USD $)	1 Months Ended
	Jul. 31, 2014
Debt Instrument [Line Items]
Other expense recognized for early redemption premium	$ 16,000,000
Early redemption amount	663,000,000
Notes Payable [Member] | Redeemable Notes Due 2024 [Member]
Debt Instrument [Line Items]
Face amount of debt issued	550,000,000
Notes issued, interest rate	3.40%
Notes Payable [Member] | Redeemable Notes Due 2054 [Member]
Debt Instrument [Line Items]
Face amount of debt issued	450,000,000
Notes issued, interest rate	4.50%
Notes Payable [Member] | Secured Equipment Notes Due October 15, 2014 [Member]
Debt Instrument [Line Items]
Face amount of debt issued	263,000,000
Notes issued, interest rate	8.375%
Notes Payable [Member] | CSX's Notes Payable Maturing April 1, 2015 [Member]
Debt Instrument [Line Items]
Face amount of debt issued	$ 400,000,000
Notes issued, interest rate	6.25%