Share-Based Compensation And Capital Stock Pretax Stock-Based Compensation Expenses And Associated Income Tax Benefits (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Pretax Stock-based Compensation Expense	$ 11.3	$ 11.2	$ 8.9
Income Tax Benefits	4.1	4.1	3.3
Stock Options
Pretax Stock-based Compensation Expense	2.1	2.8	2.4
Restricted Stock
Pretax Stock-based Compensation Expense	7.5	7.7	6.8
Performance Vested Restricted Stock Units
Pretax Stock-based Compensation Expense	1.7	0.7	(0.3)
Scenario, Adjustment [Member] | Performance Vested Restricted Stock Units
Pretax Stock-based Compensation Expense	0.5	0.1	(0.8)
Acceleration Of Award Vesting Conditions [Member] | Stock Options
Pretax Stock-based Compensation Expense		0.2
Acceleration Of Award Vesting Conditions [Member] | Restricted Stock
Pretax Stock-based Compensation Expense		$ 0.5