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Investments (Details)	9 Months Ended
	Dec. 31, 2012
Investments (Textual) [Abstract]
Investment maturity date range end	Apr. 25, 2013

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- Definition

The latest maturity date when short-term debt instruments are reported on the Schedule of Investments.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 12

-Footnote 2

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