Consolidated Statements of Shareholders' Equity (Deficit) (USD $) In Millions, unless otherwise specified	Total	Comprehensive Income (Loss)	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Beginning Balance at Dec. 31, 2008	$ 631		$ 2	$ 222	$ 965	$ (158)	$ (400)
Comprehensive income:
Net income	948	948			948
Comprehensive income		985
Other comprehensive gains (loss), defined benefit retirement plans, net of tax benefit/expense of $20, $6 and $64 for the year 2009, 2010 and 2011 respectively	37	37				37
Dividends paid $3.84, $4.25 and $5.20 per share for the year 2009, 2010 and 2011 respectively	(631)				(631)
Share repurchases	(910)						(910)
Share-based compensation	12			12
Ending Balance at Dec. 31, 2009	87		2	234	1,282	(121)	(1,310)
Comprehensive income:
Net income	1,029	1,029			1,029
Comprehensive income		1,041
Other comprehensive gains (loss), defined benefit retirement plans, net of tax benefit/expense of $20, $6 and $64 for the year 2009, 2010 and 2011 respectively	12	12				12
Dividends paid $3.84, $4.25 and $5.20 per share for the year 2009, 2010 and 2011 respectively	(645)				(645)
Share repurchases	(716)						(716)
Share-based compensation	8			8
Ending Balance at Dec. 31, 2010	(225)		2	242	1,666	(109)	(2,026)
Comprehensive income:
Net income	1,116	1,116			1,116
Comprehensive income		997
Other comprehensive gains (loss), defined benefit retirement plans, net of tax benefit/expense of $20, $6 and $64 for the year 2009, 2010 and 2011 respectively	(119)	(119)				(119)
Dividends paid $3.84, $4.25 and $5.20 per share for the year 2009, 2010 and 2011 respectively	(723)				(723)
Share repurchases	(1,586)						(1,586)
Share-based compensation	24			24
Ending Balance at Dec. 31, 2011	$ (1,513)		$ 2	$ 266	$ 2,059	$ (228)	$ (3,612)