v2.4.0.8

Summary of Short-Term Investments (Detail) (USD $) In Thousands, unless otherwise specified | Jul. 31, 2014 | Apr. 30, 2014
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | $ 67,862 | $ 40,692
Gross Unrealized Gains | 46 | 19
Gross Unrealized Losses | (10) | (11)
Fair Value | 67,898 | 40,700
Certificates of Deposit |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 7,230 | 7,466
Gross Unrealized Gains | 1 | 17
Gross Unrealized Losses | (7) | (9)
Fair Value | 7,224 | 7,474
Municipal Bonds |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 3,377 |
Gross Unrealized Gains | 31 |
Gross Unrealized Losses | (1) |
Fair Value | 3,407 |
Commercial Paper |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 5,997 |
Gross Unrealized Losses | (1) |
Fair Value | 5,996 |
US Treasury securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 51,258 | 33,226
Gross Unrealized Gains | 14 | 2
Gross Unrealized Losses | (1) | (2)
Fair Value | $ 51,271 | $ 33,226

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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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + 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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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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