Retirement and Other Postretirement Benefit Plans (Details 2) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Retirement and Other Postretirement Benefit Plans
Recognized prior service credits as a curtailment gain	$ 5.7
Net Periodic Pension Expense
Defined benefit retirement plans	(0.3)	9.0	7.8
Union sponsored multi-employer pension plan	0.9	0.7	0.6
Retirement savings plans-matching contributions	2.9	2.5	2.4
Retirement savings plans-profit sharing contributions	8.0	6.5	5.4
Net periodic expense	11.5	18.7	16.2
Net periodic cost of defined benefit retirement and postretirement plans
Curtailment gain	5.7
Net periodic pension cost	(0.3)	9.0	7.8
Change in plan assets:
Fair value of plan assets - end of year	110.8
U.S. Non-qualified Defined Benefit Retirement Plans
Retirement and Other Postretirement Benefit Plans
Expected employer contribution in next fiscal year	0.3
Net Periodic Pension Expense
Defined benefit retirement plans	4.2	3.1	3.1
Net periodic cost of defined benefit retirement and postretirement plans
Service cost	1.5	1.2	1.9
Interest cost	1.1	1.0	1.0
Net amortization	1.6	0.9	0.2
Net periodic pension cost	4.2	3.1	3.1
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Net loss (gain)	3.3
Amortization of actuarial losses	(1.5)
Amortization of prior service credit (cost)	(0.1)
Total recognized in other comprehensive income (pre-tax)	1.7
Estimated net actuarial loss to be recognized as a component of net periodic pension cost	3.0
Change in benefit obligation:
Benefit obligation - beginning of year	27.8	23.3
Service cost	1.5	1.2	1.9
Interest cost	1.1	1.0	1.0
Actuarial loss (gain)	3.3	2.9
Benefits and expenses paid	(0.3)	(0.6)
Benefit obligation - end of year	33.4	27.8	23.3
Change in plan assets:
Employer contributions	0.3	0.6
Benefits and expenses paid	(0.3)	(0.6)
Amounts recognized in Consolidated Balance Sheets:
Current liabilities	0.3	0.9
Non-current liabilities	33.1	26.9
Total Liabilities	33.4	27.8
Amounts recognized in Accumulated Other Comprehensive Income:
Actuarial net (loss) gain	(9.4)	(7.6)
Prior service credit (cost)	(0.2)	(0.3)
Total amounts recognized in accumulated other comprehensive (loss) income	(9.6)	(7.9)
Total accumulated benefit obligation	33.0	26.8
Defined benefit retirement plans and postretirement benefit plans included within accrued compensation and benefits	1.4	2.2
Defined benefit retirement plans and postretirement benefit plans included within other non-current liabilities	69.0	62.2
Expected benefit payments for the plans
2012	0.3
2013	7.1
2014	1.4
2015	18.0
2016	4.7
2017-2021	5.7
Aggregate expected benefit payments	37.2
U.S. Postretirement Plans
Retirement and Other Postretirement Benefit Plans
Expected employer contribution in next fiscal year	0.7
Net Periodic Pension Expense
Defined benefit retirement plans	0.1	0.4	0.4
Net periodic cost of defined benefit retirement and postretirement plans
Service cost		0.1	0.1
Interest cost	0.4	0.5	0.6
Net amortization	(0.3)	(0.2)	(0.3)
Net periodic pension cost	0.1	0.4	0.4
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Net loss (gain)	(1.6)
Amortization of prior service credit (cost)	0.4
Total recognized in other comprehensive income (pre-tax)	(1.2)
Change in benefit obligation:
Benefit obligation - beginning of year	9.4	11.2
Service cost		0.1	0.1
Interest cost	0.4	0.5	0.6
Plan participants' contributions	0.3	0.2
Actuarial loss (gain)	(1.5)	(1.9)
Benefits and expenses paid	(0.6)	(0.7)
Benefit obligation - end of year	8.0	9.4	11.2
Change in plan assets:
Employer contributions	0.3	0.4
Plan participants' contributions	0.3	0.3
Benefits and expenses paid	(0.6)	(0.7)
Amounts recognized in Consolidated Balance Sheets:
Current liabilities	0.7	0.8
Non-current liabilities	7.3	8.6
Total Liabilities	8.0	9.4
Amounts recognized in Accumulated Other Comprehensive Income:
Actuarial net (loss) gain	3.7	2.4
Prior service credit (cost)		0.1
Total amounts recognized in accumulated other comprehensive (loss) income	3.7	2.5
Expected benefit payments for the plans
2012	0.7
2013	0.9
2014	0.9
2015	0.8
2016	0.7
2017-2021	3.2
Aggregate expected benefit payments	7.2
European Defined Benefit Retirement Plans
Retirement and Other Postretirement Benefit Plans
Total plan assets invested in active corporate bond funds (as a percent)	34.00%
Expected long-term weighted average rate of return for next fiscal year (as a percent)	4.40%
Recognized prior service credits as a curtailment gain	5.7
Service credits recognized as a curtailment gain per diluted share (in dollars per share)	$ 0.04
Net Periodic Pension Expense
Defined benefit retirement plans	(4.5)	5.9	4.7
Net periodic cost of defined benefit retirement and postretirement plans
Service cost	1.1	3.7	3.2
Interest cost	7.2	7.3	6.1
Expected return on plan assets	(7.8)	(6.3)	(5.0)
Net amortization	0.7	1.2	0.4
Curtailment gain	5.7
Net periodic pension cost	(4.5)	5.9	4.7
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Net loss (gain)	7.9
Amortization of actuarial losses	(0.9)
Amortization of prior service credit (cost)	5.9
Effect of foreign exchange	(0.6)
Total recognized in other comprehensive income (pre-tax)	12.3
Change in benefit obligation:
Benefit obligation - beginning of year	134.1	134.6
Service cost	1.1	3.7	3.2
Interest cost	7.2	7.3	6.1
Plan participants' contributions	0.1	0.1
Actuarial loss (gain)	4.5	(2.2)
Benefits and expenses paid	(4.7)	(4.3)
Curtailment and settlements	(1.7)	(0.5)
Currency translation adjustments	(0.8)	(4.6)
Benefit obligation - end of year	139.8	134.1	134.6
Change in plan assets:
Fair value of plan assets - beginning of year	106.9	93.3
Actual return on plan assets	2.7	12.3
Employer contributions	6.2	9.0
Plan participants' contributions	0.1	0.1
Benefits and expenses paid	(4.7)	(4.3)
Currency translation adjustments	(0.4)	(3.0)
Settlement		(0.5)
Fair value of plan assets - end of year	110.8	106.9	93.3
Amounts recognized in Consolidated Balance Sheets:
Current liabilities	0.4	0.5
Non-current liabilities	28.6	26.7
Total Liabilities	29.0	27.2
Amounts recognized in Accumulated Other Comprehensive Income:
Actuarial net (loss) gain	(36.6)	(30.0)
Prior service credit (cost)	(0.1)	5.6
Total amounts recognized in accumulated other comprehensive (loss) income	(36.7)	(24.4)
Total accumulated benefit obligation	136.6	129.1
Accumulated benefit obligation in excess of plan assets	25.8	22.1
Expected benefit payments for the plans
2012	3.8
2013	3.8
2014	3.5
2015	3.7
2016	4.1
2017-2021	24.6
Aggregate expected benefit payments	43.5
United Kingdom defined benefit plan (the U.K. Plan)
Retirement and Other Postretirement Benefit Plans
Total plan assets invested in equities (as a percent)	56.00%
Expected long-term weighted average rate of return for next fiscal year (as a percent)	6.50%
Recognized prior service credits as a curtailment gain	5.7
Service credits recognized as a curtailment gain per diluted share (in dollars per share)	$ 0.04
Net periodic cost of defined benefit retirement and postretirement plans
Curtailment gain	$ 5.7