Financial Instruments (Details 3) (USD $) In Millions	Sep. 30, 2011
Maturities of available-for-sale investments in debt securities
Due in one year or less, Cost	$ 92.4
Due in one year or less, Fair Value	92.4
Due between one and two years, Cost	19.1
Due between one and two years, Fair value	19.1
Due after ten years, Cost	29.4
Due after ten years, Fair Value	25.6
Maturities of available-for-sale investments in debt securities at Cost	140.9
Maturities of available-for-sale investments in debt securities at Fair Value	$ 137.1

For an unclassified balance sheet, total of debt securities categorized neither as held-to-maturity nor trading.

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+ Details