Long-Term Borrowings (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Mar. 31, 2011
Long-Term Borrowings
Capital leases and other obligations	$ 46.3	$ 56.2
Total	842.6	354.9
Less current maturities of capital leases and other obligations (included in accrued liabilities)	(21.0)	(19.3)
Long-term borrowings	821.6	335.6
Senior unsecured notes due 2018 [Member]
Long-Term Borrowings
Senior unsecured notes	298.9	298.7
Senior unsecured notes due 2022 [Member]
Long-Term Borrowings
Senior unsecured notes	$ 497.4

Capital leases and other obligations.

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- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

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Obligation related to long-term debt (excluding convertible debt) and capital leases, the portion which is due in one year or less in the future.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Including the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

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