Income Taxes (Tables)

3 Months Ended

Mar. 31, 2015

Income Tax Disclosure [Abstract]

Schedule of Income Taxes and Effective Tax Rate

The following summarizes income tax expense (benefit) and effective tax rates:

	Three Months Ended   March 31,
millions except percentages	2015			2014
Income tax expense (benefit)	$	(1,392	)	$	664
Effective tax rate	30		%	(34		)%