v2.4.0.6

Fair Value of Financial Instruments - Additional Information (Detail) (USD $) | 12 Months Ended
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Mar. 31, 2013 | Mar. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Conversion option price per share | $ 40.60 |
Convertible Notes Payable |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Face value of debt instrument |  | $ 172,500,000
Price of stock per share when convertible notes were issued |  | $ 30.19
Closing price of stock |  | $ 45.58
Conversion option price per share |  | $ 40.60
Trading of convertible notes, face value, disclosed as a percentage | 126.00% | 116.00%

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- Definition Closing price of stock per share + References No definition available. + Details
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- Definition Convertible notes face value of trade percentage + References No definition available. + Details
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- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number APB14-1 -Paragraph 32 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Details
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- Definition Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section H + Details
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