CONSOLIDATED BALANCE SHEETS (USD $) In Millions, unless otherwise specified	Jun. 28, 2013	Dec. 28, 2012	Jun. 29, 2012	Dec. 30, 2011
Current Assets
Cash and Cash Equivalents	$ 614	$ 784	$ 642	$ 783
Short-term Investments	403	587
Accounts Receivable - Net (Note 1)	946	962
Materials and Supplies	264	274
Deferred Income Taxes	144	119
Other Current Assets	118	75
Total Current Assets	2,489	2,801
Properties	36,149	35,279
Accumulated Depreciation	(9,550)	(9,229)
Properties - Net	26,599	26,050
Other Long-term Assets	565	514
Total Assets	30,881	30,571
Current Liabilities
Accounts Payable	1,022	1,014
Labor and Fringe Benefits Payable	452	468
Casualty, Environmental and Other Reserves (Note 4)	150	140
Current Maturities of Long-term Debt (Note 7)	564	780
Income and Other Taxes Payable	111	85
Other Current Liabilities	119	140
Total Current Liabilities	2,418	2,627
Casualty, Environmental and Other Reserves (Note 4)	299	337
Long-term Debt (Note 7)	8,811	9,052
Deferred Income Taxes	8,313	8,096
Other Long-term Liabilities	1,378	1,457
Total Liabilities	21,219	21,569
Common Stock $1 Par Value	1,019	1,020
Other Capital	44	28
Retained Earnings	9,482	8,876
Accumulated Other Comprehensive Loss (Note 10)	(902)	(936)
Noncontrolling Interest	19	14
Total Shareholders' Equity	9,662	9,002
Total Liabilities and Shareholders' Equity	30,881	30,571
Investments in Conrail [Member]
Current Assets
Investment in Affiliates and Joint Ventures	709	695
Affiliates and Other Companies [Member]
Current Assets
Investment in Affiliates and Joint Ventures	$ 519	$ 511