Summarized Consolidating Cash Flow (Details) (USD $) In Millions	6 Months Ended
Jul. 01, 2011	Jun. 25, 2010
Operating Activities
Net Cash Provided by (Used in) Operating Activities	$ 1,587	$ 1,422
Investing Activities
Property Additions	(947)	(687)
Other Investing Activities	16	68
Net Cash Used in Investing Activities	(931)	(619)
Financing Activities
Long-term Debt Issued	600	0
Long-term Debt Repaid	(570)	(71)
Dividends Paid	(228)	(184)
Stock Options Exercised	24	16
Shares Repurchased	(528)	(823)
Other Financing Activities	6	(137)
Net Cash (Used in) Provided by Financing Activities	(696)	(1,199)
Net Decrease in Cash and Cash Equivalents	(40)	(396)
Cash and Cash Equivalents at Beginning of Period	1,292	1,029
Cash and Cash Equivalents at End of Period	1,252	633
CSX Corporation
Operating Activities
Net Cash Provided by (Used in) Operating Activities	300	283
Investing Activities
Property Additions	0	0
Other Investing Activities	(16)	(4)
Net Cash Used in Investing Activities	(16)	(4)
Financing Activities
Long-term Debt Issued	600
Long-term Debt Repaid	(507)	0
Dividends Paid	(233)	(188)
Stock Options Exercised	24	16
Shares Repurchased	(528)	(823)
Other Financing Activities	248	233
Net Cash (Used in) Provided by Financing Activities	(396)	(762)
Net Decrease in Cash and Cash Equivalents	(112)	(483)
Cash and Cash Equivalents at Beginning of Period	1,100	918
Cash and Cash Equivalents at End of Period	988	435
CSX Transportation
Operating Activities
Net Cash Provided by (Used in) Operating Activities	1,662	1,421
Investing Activities
Property Additions	(866)	(648)
Other Investing Activities	(95)	(47)
Net Cash Used in Investing Activities	(961)	(695)
Financing Activities
Long-term Debt Issued	0
Long-term Debt Repaid	(61)	(69)
Dividends Paid	(170)	(295)
Stock Options Exercised	0	0
Shares Repurchased	0	0
Other Financing Activities	(398)	(295)
Net Cash (Used in) Provided by Financing Activities	(629)	(659)
Net Decrease in Cash and Cash Equivalents	72	67
Cash and Cash Equivalents at Beginning of Period	118	30
Cash and Cash Equivalents at End of Period	190	97
Eliminations
Operating Activities
Net Cash Provided by (Used in) Operating Activities	(375)	(282)
Investing Activities
Property Additions	(81)	(39)
Other Investing Activities	127	119
Net Cash Used in Investing Activities	46	80
Financing Activities
Long-term Debt Issued	0
Long-term Debt Repaid	(2)	(2)
Dividends Paid	175	299
Stock Options Exercised	0	0
Shares Repurchased	0	0
Other Financing Activities	156	(75)
Net Cash (Used in) Provided by Financing Activities	329	222
Net Decrease in Cash and Cash Equivalents	0	20
Cash and Cash Equivalents at Beginning of Period	74	81
Cash and Cash Equivalents at End of Period	$ 74	$ 101

Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).

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