Stock-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Year Lawsuits Contractor Covenants	Sep. 30, 2010 Year
Pre-tax compensation expense and related income tax benefit for stock -based incentives
Long-term stock awards	$ 9	$ 9	$ 28	$ 28
Stock options	6	6	17	17
Phantom stock awards and stock appreciation rights	(5)	1	(3)
Total	10	16	42	45
Income tax benefit (before valuation allowance)	4	6	16	17
Company's long-term stock award activity
Unvested stock award shares at January 1			10,000,000	9,000,000
Weighted average grant date fair value			$ 19	$ 21
Stock award shares granted			2,000,000	3,000,000
Weighted average grant date fair value			$ 13	$ 14
Stock award shares vested			2,000,000	2,000,000
Weighted average grant date fair value			$ 20	$ 23
Stock award shares forfeited			0	0
Weighted average grant date fair value			$ 18	$ 19
Unvested stock award shares at September 30	10,000,000	10,000,000	10,000,000	10,000,000
Weighted average grant date fair value	$ 17	$ 19	$ 17	$ 19
Company's stock option activity
Option shares outstanding, January 1			37,000,000	36,000,000
Weighted average exercise price			$ 21	$ 23
Option shares granted, including restoration options			2,372,500	5,000,000
Weighted average exercise price			$ 13	$ 14
Option shares exercised			0	0
Aggregate intrinsic value on date of exercise			1	1
Weighted average exercise price			$ 8	$ 8
Option shares forfeited			2,830,000	4,000,000
Weighted average exercise price			$ 22	$ 23
Option shares outstanding, September 30	36,000,000	37,000,000	36,000,000	37,000,000
Weighted average exercise price	$ 21	$ 21	$ 21	$ 21
Weighted average remaining option term (in years)			6	6
Option shares vested and expected to vest, September 30	36,000,000	37,000,000	36,000,000	37,000,000
Weighted average exercise price	$ 21	$ 22	$ 21	$ 22
Aggregate intrinsic value	0	15	0	15
Weighted average remaining option term (in years)			6	6
Option shares exercisable (vested), September 30	24,000,000	22,000,000	24,000,000	22,000,000
Weighted average exercise price	$ 24	$ 25	$ 24	$ 25
Aggregate intrinsic value			0	3
Weighted average remaining option term (in years)			4	4
Weighted average grant date fair value of option shares granted and the assumptions used to estimate those values using a black-scholes option pricing model
Weighted average grant date fair value			$ 5.10	$ 5.30
Risk-free interest rate			2.72%	2.77%
Dividend yield			2.34%	2.17%
Volatility factor			49.00%	46.01%
Expected option life (in years)			6	6
Stock-Based Compensation (Textuals) (Abstract)
Typical vesting period of stock awards granted prior to January 1, 2010			10 years
Stock awards granted subsequent to January 1, 2010 have a vesting period, in years			5 years
Total unrecognized compensation expense	122	136	122	136
Remaining weighted average vesting period			5	5
Total market value (at the vesting date) of stock award shares			28	22
Grant and expire date			Not later than 10 years
Stock option shares granted			2,372,500	5,000,000
Approx grant date exercise price			$ 13
Stock option shares forfeited			2,830,000	4,000,000
Unrecognized compensation expense related to unvested stock options	$ 39	$ 50	$ 39	$ 50
Weighted average vesting period for unvested stock options			3	3