Stock-Based Compensation Plans (Performance-Based Restricted Stock-Units) (Details) (Performance Shares [Member], USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012
Performance Shares [Member]
Non-vested, beginning balance, shares		0.9
Non-vested, beginning balance, weighted average fair value at date of grant		$ 12.69
Granted, shares	0.1	0.1	0.6
Granted, weighted average fair value at date of grant	$ 16.34		$ 12.93
Vested, shares	(0.7)
Vested, weighted average fair value at date of grant	$ 13.22
Forfeited, shares	0
Forfeited, weighted average fair value at date of grant	$ 0.00
Non-vested, ending balance, shares	0.3	0.3
Non-vested, ending balance, weighted average fair value at date of grant	$ 12.90	$ 12.90