Consolidated Statements of Income (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues	$ 5,735	$ 5,322	$ 11,182	$ 10,606
Operating expenses:
Compensation and benefits	1,234	1,128	2,452	2,267
Fuel	1,156	1,076	2,315	2,198
Purchased services	634	617	1,287	1,234
Depreciation and amortization	523	489	1,038	972
Equipment rents	225	205	440	403
Materials and other	283	230	602	487
Total operating expenses	4,055	3,745	8,134	7,561
Operating income	1,680	1,577	3,048	3,045
Interest expense	206	177	402	355
Other expense, net	2	3	5	4
Total before tax	1,472	1,397	2,641	2,686
Income tax expense	556	513	1,001	1,004
Net income	$ 916	$ 884	$ 1,640	$ 1,682