Investments (Details 1) (Debt Securities [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Debt Securities [Member]
Contractual Maturities for Available-for-sale investment in debt securities
Available-for-Sale Securities, at cost due within one year	$ 9.0
Available-for-Sale Securities, at cost due in one to five years	43.6
Available-for-Sale Securities, at cost	52.6
Available-for-Sale Securities, Due within one year at fair value	9.0
Available-for-Sale Securities, Due in one to five years at fair value	43.9
Available-for-Sale Securities, at fair value	$ 52.9

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at cost, net of adjustments, which include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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