Stock-Based Compensation (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Pre-tax stock-based compensation	$ 8.1	$ 11.7	$ 26.6	$ 28.4
Performance Based Restricted Stock Units (RSU) [Member]
Performance-based stock units awarded			1.0
Vesting period, years			3
Percentage of units that are earned, minimum			0.00%
Percentage of units that are earned, maximum			200.00%
Performance-based stock, outstanding	2.1		2.1
Shares entitled to recipients			1.5
Percentage of units granted assumed			100.00%
PSU Other Than TSR [Member]
Performance-based stock units awarded		0.7
Non-TSR PSU Vesting Period Minimum		2
Non-TSR PSU Vesting Period Maximum		7
Performance-based stock, outstanding	0.7		0.7