Debt (Short Term Debt Narrative) (Details) (USD $) In Millions, unless otherwise specified					1 Months Ended	12 Months Ended				12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Sep. 30, 2012 Accounts Receivable Securitization Facility [Member]	Dec. 31, 2012 Accounts Receivable Securitization Facility [Member]	Dec. 31, 2012 4 percent Convertible Senior Notes [Member]	Dec. 31, 2011 4 percent Convertible Senior Notes [Member]	Nov. 30, 2009 4 percent Convertible Senior Notes [Member]	Dec. 31, 2012 $1.9 billion ABL Facility [Member]	Sep. 30, 2012 Original Terms [Member] Accounts Receivable Securitization Facility [Member]	Dec. 31, 2012 Original Terms [Member] $1.9 billion ABL Facility [Member]	Sep. 30, 2012 Amended Terms [Member] Accounts Receivable Securitization Facility [Member]	Dec. 31, 2012 Amended Terms [Member] $1.9 billion ABL Facility [Member]	Dec. 31, 2012 Subsidiaries [Member]	Dec. 31, 2011 Subsidiaries [Member]	Dec. 31, 2012 Subsidiaries [Member] Accounts Receivable Securitization Facility [Member]		Dec. 31, 2011 Subsidiaries [Member] Accounts Receivable Securitization Facility [Member]		Dec. 31, 2012 Subsidiaries [Member] $1.9 billion ABL Facility [Member]		Dec. 31, 2011 Subsidiaries [Member] $1.9 billion ABL Facility [Member]		Dec. 31, 2012 Parent Company [Member] 4 percent Convertible Senior Notes [Member]		Dec. 31, 2011 Parent Company [Member] 4 percent Convertible Senior Notes [Member]
Short-term Debt [Line Items]
Total debt	$ 7,309	[1]	$ 2,987	[1]											$ 7,172	$ 2,858	$ 453	[2]	$ 255	[2]	$ 1,184	[2]	$ 810	[2]	$ 137	[3]	$ 129
Stated interest rate							4.00%	4.00%	4.00%
Average outstanding amount						315
Interest rate during period						0.90%
Maximum month-end outstanding amount						475
Line of credit facility, maximum borrowing capacity											300	1,250	475	1,900
Extension period					364 days
Collateral amount						536
Line of credit facility, average outstanding amount										1,138
Line of credit facility, interest rate during period										2.30%
Line of credit facility, maximum month-end outstanding amount										$ 1,287

[1] In August 1998, a subsidiary trust of Holdings (the “Trust”) issued and sold $300 of 6 1/2 percent Convertible Quarterly Income Preferred Securities (“QUIPS”) in a private offering. The Trust used the proceeds from the offering to purchase 6 1/2 percent subordinated convertible debentures due 2028 (the “Debentures”), which resulted in Holdings receiving all of the net proceeds of the offering. The QUIPS are non-voting securities, carry a liquidation value of $50 (fifty dollars) per security and are convertible into Holdings’ common stock. Total long-term debt at December 31, 2012 and 2011 excludes $55 of these Debentures, which are separately classified in our consolidated balance sheets and referred to as “subordinated convertible debentures.” The subordinated convertible debentures reflect the obligation to our subsidiary that has issued the QUIPS. This subsidiary is not consolidated in our financial statements because we are not the primary beneficiary of the Trust. See note 13 (“Subordinated Convertible Debentures”) for additional detail.

[2] $654 and $22 were available under our ABL facility and accounts receivable securitization facility, respectively, at December 31, 2012. The ABL facility availability is reflected net of $62 of letters of credit. At December 31, 2012, the interest rates applicable to our ABL facility and accounts receivable securitization facility were 2.3 percent and 0.9 percent, respectively.

[3] The fair value of the 4 percent Convertible Senior Notes is based on the market value of comparable notes. Consistent with the carrying amount, the fair value excludes the equity component of the notes. To exclude the equity component and calculate the fair value, we used an effective interest rate of 6.9 percent.