Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenues	$ 4,767	$ 5,602
Operating expenses:
Compensation and benefits	1,208	1,338
Purchased services	638	648
Depreciation and amortization	520	496
Fuel	395	713
Equipment rents	188	191
Materials and other	313	322
Total operating expenses	3,262	3,708
Operating income	1,505	1,894
Interest expense	245	217
Other expense, net	2	5
Income before income taxes	1,258	1,672
Income tax expense	474	627
Net income	$ 784	$ 1,045