Share-Based Compensation Plans (Schedule of Summary of Stock Options) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Outstanding, beginning balance, in shares	28,361
Granted, in shares	1,775
Exercised, in shares	(556)
Forfeited, in shares	(377)
Expired, in shares	(2,913)
Outstanding, ending balance, in shares	26,290
Exercisable, ending balance, in shares	22,580
Outstanding, beginning balance, weighted-average exercise price	$ 31.30
Granted, weighted-average exercise price	$ 18.24
Exercised, weighted-average exercise price	$ 15.50
Forfeited, weighted-average exercise price	$ 23.63
Expired, weighted-average exercise price	$ 29.69
Outstanding, ending balance, weighted-average exercise price	$ 31.00
Exercisable, ending balance, weighted-average exercise price	$ 31.76
Outstanding, ending balance, weighted-average contractual term, years	4 years 3 months 18 days
Outstanding, exercisable, weighted-average contractual term, years	3 years 9 months 18 days
Outstanding, ending balance, aggregate intrinsic value	$ 2.2
Exercisable, ending balance, aggregate intrinsic value	$ 0.1