Fair Value Measurement (Details)	6 Months Ended
Sep. 30, 2012
Fair Value, Level 3 Transfers in, Description	There were no transfers of assets in to or out of Level 3 for the three and six months ended September 30, 2012.

Disclosures concerning the reasons for transfers into Level 3 of the fair value hierarchy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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