Income Taxes Effective Rate (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Tax Disclosure [Abstract]
Statutory U.S. federal income tax rate		35.00%	35.00%	35.00%
Changes In Unrecognized Tax Positions		$ 1.4
State income taxes, net of federal tax benefit		1.70%	1.60%	1.70%
Benefits and taxes related to foreign operations		(3.40%)	(2.70%)	(2.40%)
Unrecognized tax benefits		(0.80%)	1.30%	(0.30%)
Adjustment to deferred taxes, prior years		(0.90%)	(2.10%)	0.00%
Other		(1.50%)	(1.00%)	0.80%
Effective income tax rates		30.10%	32.10%	34.80%
Income Tax Reconciliation, Tax Credits, Foreign	1.7	2.8	1.6
Tax Adjustments, Settlements, and Unusual Provisions		1.4
Income Tax Reconciliation, Tax Contingencies			1.6
Income Tax Reconciliation, Change in Deferred Tax Assets Valuation Allowance			$ 3.3