Summary of Significant Accounting Policies (Details 6) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of Significant Accounting Policies
Reclassifications of cumulative currency translation adjustments into earnings			$ (87,900,000)
Components of accumulated other comprehensive income (loss), net of applicable income taxes
Unrealized foreign currency translation gains	9,200,000	4,800,000
Net loss from pension and other postretirement benefit liabilities (net of income tax benefits of $25.3 million and $27.2 million, respectively)	(59,100,000)	(44,500,000)
Unrealized gain on "available-for-sale" securities	100,000
Accumulated other comprehensive loss	(49,800,000)	(39,700,000)
Income tax benefits related to net loss from pension and other postretirement benefit liabilities	$ 34,900,000	$ 27,200,000