Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 2,728	$ 2,384
Accounts receivable, net	1,279	1,386
Materials and supplies	852	795
Current portion of deferred income taxes	241	355
Other current assets	224	232
Total current assets	5,324	5,152
Property and equipment, net of accumulated depreciation of $4,385 and $3,550, respectively	57,323	55,806
Goodwill	14,819	14,819
Intangible assets, net	474	512
Other assets	2,007	1,914
Total assets	79,947	78,203
Current liabilities:
Accounts payable and other current liabilities	3,390	3,435
Long-term debt due within one year	326	366
Total current liabilities	3,716	3,801
Long-term debt	20,590	18,914
Deferred income taxes	18,174	18,001
Intangible liabilities, net	721	782
Casualty and environmental liabilities	617	639
Pension and retiree health and welfare liability	380	385
Other liabilities	1,008	947
Total liabilities	$ 45,206	$ 43,469
Commitments and contingencies (see Notes 6 and 7)
Equity:
Member's equity	$ 34,744	$ 34,736
Accumulated other comprehensive income	(3)	(2)
Total equity	34,741	34,734
Total liabilities and equity	$ 79,947	$ 78,203