Indebtedness (Summary Of Total Indebtedness) (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Debt Instrument [Line Items]
Current portion	$ (43.1)	$ (11.3)
Total debt	1,244.0	1,239.6
Total long-term debt	1,200.9	1,228.3
Derivatives assets	8.7	2.0
Series 2005 - 1 Swap [Member] \| Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Derivatives assets	8.0	(3.7)
Series 2005-1 Notes [Member]
Debt Instrument [Line Items]
Notes payable	308.0	296.3
Series 2007-1 Notes [Member]
Debt Instrument [Line Items]
Notes payable	300.0	300.0
2008 Term Loan [Member]
Debt Instrument [Line Items]
Loan Payable	138.8	146.3
2010 Senior Notes [Member]
Debt Instrument [Line Items]
Notes payable	497.2	497.0
Unamortized discount	$ 2.8	$ 3.0

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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