Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 2,555	$ 2,225
Accounts receivable, net	1,307	1,298
Materials and supplies	859	835
Current portion of deferred income taxes	195	358
Other current assets	168	87
Total current assets	5,084	4,803
Property and equipment, net of accumulated depreciation of $2,632 and $2,232, respectively	52,833	52,363
Goodwill	14,819	14,819
Intangible assets, net	744	821
Other assets	2,289	2,224
Total assets	75,769	75,030
Current liabilities:
Accounts payable and other current liabilities	3,246	3,206
Long-term debt due within one year	389	645
Total current liabilities	3,635	3,851
Long-term debt	17,560	16,361
Deferred income taxes	17,120	17,224
Intangible liabilities, net	917	961
Casualty and environmental liabilities	673	677
Pension and retiree health and welfare liability	360	362
Other liabilities	915	982
Total liabilities	41,180	40,418
Commitments and contingencies (see Notes 5 and 6)
Equity:
Member's Equity	34,341	34,367
Accumulated other comprehensive loss	248	245
Total equity	34,589	34,612
Total liabilities and equity	$ 75,769	$ 75,030