v2.4.0.8

Summary of Short-Term Investments (Detail) (USD $) In Thousands, unless otherwise specified | Apr. 30, 2014 | Apr. 30, 2013
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | $ 40,692 | $ 70,370
Gross Unrealized Gains | 19 | 24
Gross Unrealized Losses | (11) | (104)
Fair Value | 40,700 | 70,290
Certificates of Deposit |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 7,466 | 9,230
Gross Unrealized Gains | 17 | 9
Gross Unrealized Losses | (9) | (4)
Fair Value | 7,474 | 9,235
U.S. Treasury securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 33,226 | 61,140
Gross Unrealized Gains | 2 | 15
Gross Unrealized Losses | (2) | (100)
Fair Value | $ 33,226 | $ 61,055

X
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- Definition This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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