Credit Facilities and Long-Term Debt (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Credit Facilities and Long-Term Debt :
Short-term borrowings and current maturities of long-term debt	$ 89		$ 42
Unamortized discount	(1)	[1]	(1)	[1]
Long-term debt	1,199		1,199
Total debt	1,288		1,241
Senior Notes Due 2016, 3.550%
Credit Facilities and Long-Term Debt :
Senior Notes Due	600	[2]	600	[2]
Senior Notes Due 2021, 4.875%
Credit Facilities and Long-Term Debt :
Senior Notes Due	$ 600	[2]	$ 600	[2]

[1] The unamortized discount is recognized as a reduction in the carrying value of the Senior Notes in the Consolidated Balance Sheets and is being amortized to interest expense in our Consolidated Income Statements over the expected remaining terms of the Senior Notes.

[2] The fair value of our Senior Notes (as defined below) was determined using quoted prices in active markets for identical securities, which are considered Level 1 inputs. The fair value of our Senior Notes due 2016 (as defined below) was $621 million and $635 million as of December 31, 2014 and 2013, respectively. The fair value of our Senior Notes due 2021 (as defined below) was $653 million and $629 million as of December 31, 2014 and 2013, respectively.