Financial Instruments (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Mar. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss on available-for-sale auction rate securities	$ (0.4)	$ (0.2)
Financial Instruments (Textual) [Abstract]
Discount rate used in internally developed models, minimum	3.90%
Discount rate used in internally developed models, maximum	4.10%
Discount rate used in internally developed models, weighted average	4.00%
Redemption of available-for-sale holdings by issuers of auction rate securities	7.6	0.2
Guarantee by the federal government for bonds issued by public agencies	97.00%		97.00%
Foreign currency forward contracts that closed in a gain position	0.9		8.1
Foreign currency forward contracts that closed in a loss position	5.3		0.6
Specific finance receivables fully reserved	0.3
Trade finance receivables transferred to financial institutions on a non-recourse basis	72.8	11.1
Finance receivables	115.6
Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value of Auction rate securities held Available-for-sale securities in auction rate securities held	21.7		29.3
Fair value of available-for-sale auction rate securities	18.7		26.9
Unrealized loss on available-for-sale auction rate securities	3.0
Foreign Currency Foreign Exchange Contracts [Member]
Derivative [Line Items]
Effect of foreign currency forward contracts	6.4	(3.7)
Net effect of foreign currency forward contracts after including gains and losses on foreign currency exposure	(0.4)	(1.0)
Senior unsecured notes due 2022 [Member]
Debt Instrument [Line Items]
Fair value of senior unsecured notes	514.0		506.6
Carrying value of senior unsecured notes	497.5		497.4
Senior unsecured notes due 2018 [Member]
Debt Instrument [Line Items]
Fair value of senior unsecured notes	365.1		368.4
Carrying value of senior unsecured notes	$ 298.9		$ 298.9

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Guarantee for bonds issued by public agencies

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Redemption of available-for-sale holdings by issuers of auction rate securities.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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The amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

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