v2.4.0.8

Components of Net Deferred Tax Amounts Recognized in Accompanying Consolidated Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified | Apr. 30, 2014 | Apr. 30, 2013
--- | --- | ---
Deferred tax asset: |  |
Bad debts | $ 743 | $ 761
Other accruals | 2,165 | 2,158
Charitable contributions | 274 | 216
Stock options | 4,829 | 3,476
State tax credit | 554 | 15
Net operating losses | 58,536 | 45,309
Research and development credit | 3,497 | 3,169
Deferred rent | 671 | 1,045
Deferred revenue | 1,175 | 1,694
Total deferred tax asset | 72,444 | 57,843
Less valuation allowance | (52,734) | (37,902)
Net deferred tax assets | 19,710 | 19,941
Deferred tax liability: |  |
Amortization of intangible assets | (15,190) | (16,756)
Depreciation | (4,517) | (3,152)
Total deferred tax liability | (19,707) | (19,908)
Total net deferred tax assets | $ 3 | $ 33

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