Stock-Based Compensation (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Pre-tax compensation expense and related income tax benefit for stock -based incentives
Long-term stock awards	$ 9	$ 9	$ 19	$ 19
Stock options	6	6	11	11
Phantom stock awards and stock appreciation rights	(1)	(4)	2	(1)
Total	14	11	32	29
Income tax benefit	5	4	12	11
Company's long-term stock award activity
Unvested stock award shares at January 1			10	9
Weighted average grant date fair value			$ 19	$ 21
Stock award shares granted			2	3
Weighted average grant date fair value			$ 13	$ 14
Stock award shares vested			1	1
Weighted average grant date fair value			$ 19	$ 23
Stock award shares forfeited			0
Weighted average grant date fair value			$ 18	$ 20
Unvested stock award shares at June 30	11	11	11	11
Weighted average grant date fair value	$ 17	$ 19	$ 17	$ 19
Company's stock option activity
Option shares outstanding, January 1			37	36
Weighted average exercise price			$ 21	$ 23
Option shares granted, including restoration options			2	5
Weighted average exercise price			$ 13	$ 14
Option shares exercised			0
Aggregate intrinsic value on date of exercise (A)			1	1
Weighted average exercise price			$ 8	$ 8
Option shares forfeited			2	3
Weighted average exercise price			$ 22	$ 23
Option shares outstanding, June 30	37	38	37	38
Weighted average exercise price	$ 21	$ 21	$ 21	$ 21
Weighted average remaining option term (in years)			6	6
Option shares vested and expected to vest, June 30	37	37	37	37
Weighted average exercise price	$ 21	$ 21	$ 21	$ 21
Aggregate intrinsic value	20	14	20	14
Weighted average remaining option term (in years)			6	6
Option shares exercisable (vested), June 30	24	22	24	22
Weighted average exercise price	$ 24	$ 25	$ 24	$ 25
Aggregate intrinsic value			8	3
Weighted average remaining option term (in years)			5	5
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 January1, 2010 have a vesting period, in years			5 years
Total unrecognized compensation expense	134	145	134	145
Remaining weighted average vesting period			5	6
Total market value (at the vesting date) of stock award shares			23	17
Grant and expire date			Not later than 10 years
Stock option shares granted			2	5
Approx grant date exercise price			$ 13
Stock option shares forfeited			2	3
Unrecognized compensation expense related to unvested stock options	$ 45	$ 56	$ 45	$ 56
Weighted average vesting period for unvested stock options			3	3