Income Taxes (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010 Jurisdictions	Dec. 31, 2009
Income before income taxes:
U.S.	$ 106.3	$ 54.3	$ 63.6
International	69.2	45.5	14.0
Total income before income taxes	175.5	99.8	77.6
Current:
U.S.	10.6	1.1	1.5
International	7.6	5.7	0.9
Current provision for income taxes	18.2	6.8	2.4
Deferred:
U.S.	24.4	15.1	23.8
International	(1.0)	1.0	(4.2)
Deferred provision (benefit) for income taxes	23.4	16.1	19.6
Total provision for income taxes	41.6	22.9	22.0
U.S. federal statutory income tax rate (as a percent)	35.00%
Reconciliation of provision for income taxes at U.S. federal statutory income tax rate to effective income tax rate
Provision for taxes at U.S. federal statutory rate	61.5	34.9	27.1
State and local taxes, net of federal benefit	2.2	1.8	1.6
Foreign effective rate differential	(8.4)	(7.3)	(7.4)
Other	1.3	1.4	(0.7)
Foreign Tax Credit Carryforward	(2.4)	(3.2)	1.4
U.S. Research & Development Tax Credits	(1.0)	(1.3)	(2.0)
Wind Energy Tax Credit	(0.1)	(3.5)
Tax Settlement	(5.5)
Change in valuation allowance	(6.0)	0.1	2.0
Total provision for income taxes	41.6	22.9	22.0
Number of foreign jurisdictions in which provision reflects the favorable impact of a tax audit settlement		1
Assets
Net operating loss carryforwards	64.2	61.8
Unfunded pension liability and other postretirement obligations	13.8	14.5
Accelerated amortization		7.4
Advanced payments from foreign affiliates	18.8
Tax credit carryforwards	21.0	34.4
Stock based compensation	11.3	9.0
Other comprehensive income	13.4	8.8
Reserves and other	14.7	15.4
Subtotal	157.2	151.3
Valuation allowance	(39.4)	(36.5)
Total assets	117.8	114.8
Liabilities
Accelerated depreciation	(39.4)	(29.0)
Accelerated amortization	(1.2)
Other	(0.4)	(0.8)
Total liabilities	(41.0)	(29.8)
Net deferred tax assets	76.8	85.0
Deferred tax assets and deferred tax liabilities as presented in consolidated balance sheets
Current deferred tax assets, net	45.1	23.3
Current deferred tax liability, net	(0.1)	(0.1)
Long-term deferred tax assets, net	33.0	63.6
Long-term deferred tax liability, net	(1.2)	(1.8)
Net deferred tax assets	$ 76.8	$ 85.0