Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

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Represents the impact on both basic and diluted net income per common share for recognition of total stock-based compensation expense.

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The cash charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

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Represents the number of stock incentive plans maintained by the entity.

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Accounting Policies (Details 5) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended			1 Months Ended	12 Months Ended
	Dec. 31, 2011 plan Y	Dec. 31, 2010	Dec. 31, 2009	Jan. 31, 2011 Chief Executive Officer	Dec. 31, 2011 Stock options	Dec. 31, 2010 Stock options	Dec. 31, 2009 Stock options	Dec. 31, 2011 Other stock-based plans	Dec. 31, 2010 Other stock-based plans	Dec. 31, 2009 Other stock-based plans
Stock-based compensation
Tax benefit recorded for the compensation expense					$ 0.6	$ 0.6	$ 0.6	$ 1.5	$ 1.2	$ 1.2
Number of stock-based compensation plans	3
Total unrecognized compensation costs related to unvested stock-based compensation arrangements	10.6
Total weighted average remaining term of unrecognized compensation costs (in years)	2.4
Compensation cost recognized in selling, general and administrative expenses	5.3	4.7	4.9
Charges related to separation agreement with company's former CEO				6.3
Expected cash severance charge				3.3
Expected non-cash severance charge				$ 3.0
Impact on both basic and diluted net income per common share for recognition of total stock-based compensation expense (in dollars per share)	$ 0.09	$ 0.08	$ 0.08