Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Tax Provision [Abstract]
Forecasted tax expense by jurisdiction			$ 167	$ 134
Adjustments to income tax provision [Abstract]
Tax effect of goodwill impairment			9	0
Finalization of prior year returns			4	6
Tax effects of changes in legislation			0	(9)
Changes in valuation allowances			3	5
Accrual adjustments and other			(4)	0
Tax provision	$ 70	$ 49	$ 179	$ 136
Tax Rate [Abstract]
Forecasted tax expense by jurisdiction (in hundredths)			22.70%	23.30%
Adjustments to income tax provision [Abstract]
Tax effect of goodwill impairment (in hundredths)			1.30%	0.00%
Finalization of prior year returns (in hundredths)			0.50%	1.00%
Tax effects of changes in legislation (in hundredths)			0.00%	(1.60%)
Changes in valuation allowances (in hundredths)			0.40%	1.00%
Accrual adjustments and other (in hundredths)			(0.50%)	0.00%
Tax provision (in hundredths)			24.40%	23.70%