Financing Agreements - Schedule of Debt (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Total	$ 1,602	$ 859
Less: current maturities	34	56
Total long-term debt	1,568	803
Senior Notes Due February 2019 [Member]
Debt Instrument [Line Items]
Senior notes issued, interest rate	6.50%
Total	400	400
Senior Notes Due February 2021 [Member]
Debt Instrument [Line Items]
Senior notes issued, interest rate	6.75%
Total	350	350
Senior Notes Due September 2021 [Member]
Debt Instrument [Line Items]
Senior notes issued, interest rate	5.375%
Total	450
Senior Notes Due September 2023 [Member]
Debt Instrument [Line Items]
Senior notes issued, interest rate	6.00%
Total	300
Other Indebtedness
Debt Instrument [Line Items]
Total	$ 102	$ 109