Consolidated Statements of Shareholders' Equity (unaudited) (USD $) In Millions	Total	Common Stock	Additional Paid in Capital	Accumulated Other Comprehensive Loss	Treasury Stock at Cost	Retained Earnings
Balance at Beginning of Period at Dec. 31, 2011	$ 7,265	$ 656	$ 2,497	$ (100)	$ (638)	$ 4,850
Net Income	263	0	0	0	0	263
Stock-based Compensation	16	0	16	0	0	0
Exercise of Stock Options	27	2	25	0	0	0
Tax Benefits Related to Exercise of Stock Options	12	0	12	0	0	0
Dividends	(39)	0	0	0	0	(39)
Changes in Treasury Stock, Net	(13)	0	0	0	(13)	0
Net Change in Pension and Other	2	1	(1)	2	0	0
Balance at End of Period at Mar. 31, 2012	7,533	659	2,549	(98)	(651)	5,074
Balance at Beginning of Period at Dec. 31, 2012	8,258	2	3,304	(113)	(648)	5,713
Net Income	261	0	0	0	0	261
Stock-based Compensation	18	0	18	0	0	0
Exercise of Stock Options	22	0	22	0	0	0
Tax Benefits Related to Exercise of Stock Options	9	0	9	0	0	0
Dividends	(44)	0	0	0	0	(44)
Changes in Treasury Stock, Net	(14)	0	0	0	(14)	0
Net Change in Pension and Other	4	0	0	4	0	0
Balance at End of Period at Mar. 31, 2013	$ 8,514	$ 2	$ 3,353	$ (109)	$ (662)	$ 5,930