Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	11 Months Ended	12 Months Ended		1 Months Ended
	Dec. 31, 2010 Successor	Dec. 31, 2012 Successor	Dec. 31, 2011 Successor	Feb. 12, 2010 Predecessor
OPERATING ACTIVITIES
Net income	$ 2,235	$ 3,372	$ 2,972	$ 224
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,532	1,889	1,807	192
Deferred income taxes	710	660	1,509	127
Long-term casualty and environmental liabilities, net	(25)	(190)	(43)	(2)
Contributions to defined benefit pension plan	(400)	(36)	(36)	0
Other, net	(204)	(314)	(249)	(78)
Changes in current assets and liabilities:
Accounts receivable, net	(118)	(6)	(219)	(21)
Materials and supplies	(23)	(61)	(87)	3
Other current assets	104	14	(15)	(123)
Accounts payable and other current liabilities	484	105	301	(243)
Net cash provided by operating activities	4,295	5,433	5,940	79
INVESTING ACTIVITIES
Capital expenditures excluding equipment	(1,953)	(2,596)	(2,726)	(160)
Acquisition of equipment	(445)	(952)	(763)	(67)
Partnership Investment	(443)	(130)	0	0
Other, net	(76)	(158)	33	76
Net cash used for investing activities	(2,917)	(3,836)	(3,456)	(151)
FINANCING ACTIVITIES
Proceeds from issuance of long-term debt	1,500	2,500	1,500	0
Payments on long-term debt	(493)	(482)	(596)	(30)
Cash distributions/dividends paid	(1,250)	(3,750)	(3,500)	(226)
Proceeds from Stock Options Exercised	0	0	0	21
Excess Tax Benefit from equity compensation plans	0	0	0	9
Other, net	(19)	(31)	(15)	0
Net cash used for financing activities	(262)	(1,763)	(2,611)	(226)
Increase/(decrease) in cash and cash equivalents	1,116	(166)	(127)	(298)
Cash and cash equivalents:
Beginning of period	971	1,960	2,087	1,269
End of period	2,087	1,794	1,960	971
SUPPLEMENTAL CASH FLOW INFORMATION
Interest paid, net of amounts capitalized	539	707	666	97
Capital investments accrued but not yet paid	170	123	190	60
Income taxes paid, net of refunds	665	1,194	(13)	0
Non-cash asset financing	$ 40	$ 0	$ 1	$ 8