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Stockholders' Equity (Tables) | 12 Months Ended
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Apr. 30, 2013
Summary of the Grant Activity for Stock Options, Restricted Stock Units, Performance Stock Units and Restricted Stock Awards | The following table summarizes the grant activity for stock options, restricted stock units, performance stock units and restricted stock awards for the fiscal years ended April 30, 2013, 2012 and 2011, respectively:
|  | Granted |  |  | Weighted Average Grant Date Fair Value |  |  | Unissued at April 30, 2013 |
Fiscal year 2011 grants |  |  |  |  |  |  |  |  |  |  |  |
Stock options |  |  | 280 |  |  | $ | 2.85 |  |  |  | 250 |
Restricted stock units |  |  | 499 |  |  | $ | 3.57 |  |  |  | 83 |
Performance stock units (1) |  |  | 469 |  |  | $ | 4.20 |  |  |  | - |
Restricted stock awards |  |  | 62 |  |  | $ | 4.81 |  |  |  | - |
Total |  |  | 1,310 |  |  |  |  |  |  |  | 333 |
Fiscal year 2012 grants |  |  |  |  |  |  |  |  |  |  |  |
Stock options |  |  | 7 |  |  | $ | 4.14 |  |  |  | 7 |
Restricted stock units |  |  | 305 |  |  | $ | 6.12 |  |  |  | 143 |
Performance stock units (1) |  |  | 255 |  |  | $ | 6.06 |  |  |  | 196 |
Restricted stock awards |  |  | 51 |  |  | $ | 5.83 |  |  |  | - |
Total |  |  | 618 |  |  |  |  |  |  |  | 346 |
Fiscal year 2013 grants |  |  |  |  |  |  |  |  |  |  |  |
Stock options |  |  | 388 |  |  | $ | 3.03 |  |  |  | 388 |
Restricted stock units |  |  | 340 |  |  | $ | 5.15 |  |  |  | 273 |
Performance stock units (1) |  |  | 316 |  |  | $ | 5.17 |  |  |  | 259 |
Restricted stock awards |  |  | 79 |  |  | $ | 4.45 |  |  |  | - |
Total |  |  | 1,123 |  |  |  |  |  |  |  | 920 |
(1) | Performance stock units are included at the 100% attainment level.
Summary of Stock Options, Restricted Stock and Restricted / Performance Stock Units Outstanding | A summary of stock options, restricted stock and restricted / performance stock units outstanding as of April 30, 2013 and 2012, and changes during the fiscal year ended April 30, 2013, is presented below:
|  | Unvested Options |  |  | Vested Options |  |  | Total Options |  |  | Weighted Average Exercise Price |  |  | Aggregate Intrinsic Value of Vested Options |  |  | Weighted Average Remaining Term (Years) |  |  | Restricted Stock Units, Restricted Stock and Performance Stock Units Unvested (1) |
Outstanding, April 30, 2012 |  |  | 174 |  |  |  | 1,487 |  |  |  | 1,661 |  |  | $ | 10.55 |  |  | $ | 592 |  |  |  | 3.6 |  |  |  | 1,380 |
Granted |  |  | 388 |  |  |  | - |  |  |  | 388 |  |  |  | 4.10 |  |  |  |  |  |  |  |  |  |  |  | 735 |
Vested (options only) (2) |  |  | (125) |  |  |  | 125 |  |  |  | - |  |  |  | 4.08 |  |  |  |  |  |  |  |  |  |  |  | - |
Forfeited |  |  | - |  |  |  | (607) |  |  |  | (607) |  |  |  | 11.37 |  |  |  |  |  |  |  |  |  |  |  | (533) |
Exercised/Issued |  |  | - |  |  |  | - |  |  |  | - |  |  |  | - |  |  |  |  |  |  |  |  |  |  |  | (494) |
Outstanding, April 30, 2013 |  |  | 437 |  |  |  | 1,005 |  |  |  | 1,442 |  |  |  | 8.48 |  |  |  | 240 |  |  |  | 5.3 |  |  |  | 1,088 |
Exercisable, April 30, 2011 |  |  |  |  |  |  | 1,998 |  |  |  | 1,998 |  |  | $ | 11.80 |  |  | $ | 52 |  |  |  | 3.1 |  |  |  |  |
Exercisable, April 30, 2012 |  |  |  |  |  |  | 1,487 |  |  |  | 1,487 |  |  | $ | 11.33 |  |  | $ | 222 |  |  |  | 3.1 |  |  |  |  |
Exercisable, April 30, 2013 |  |  |  |  |  |  | 1,005 |  |  |  | 1,005 |  |  | $ | 10.41 |  |  | $ | 94 |  |  |  | 3.7 |  |  |  |  |
Expected to vest at April 30, 2013 |  |  | 436 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 958 |
(1) | Performance stock units are included at the 100% attainment level. Attainment of performance metrics at maximum levels could result in the issuance of an additional 357 shares of Class A common stock.
(2) | The total fair value of the 125 stock options vested during the fiscal year and outstanding as of April 30, 2013 was approximately $378.
Schedule of Fair Value of Stock Options Weighted Average Assumptions | The fair values of our stock option grants and shares to be purchased under our Employee Stock Purchase Plan were estimated assuming no expected dividend yield using the following weighted average assumptions for the fiscal years ended April 30, 2013, 2012 and 2011:
|  | Fiscal Year Ended April 30,
|  | 2013 |  | 2012 |  | 2011
Stock Options: |  |  |  |  |  |
Expected life |  | 6.82 years |  | 5.5 years |  | 6.5 years
Risk-free interest rate |  | 1.14% |  | 0.82% |  | 1.80%
Expected volatility |  | 84.40% |  | 91.54% |  | 85.59%
Schedule of Fair Values of Employee Stock Purchase Plan Weighted Average Assumptions |
Stock Purchase Plan: |  |  |  |  |  |
Expected life |  | 0.5 years |  | 0.5 years |  | 0.5 years
Risk-free interest rate |  | 0.12% |  | 0.10% |  | 0.20%
Expected volatility |  | 46.95% |  | 49.05% |  | 46.53%

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- Definition Tabular disclosure of the number, intrinsic value, weighted-average remaining term and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year and the number of share options (or share units) that were granted, exercised or converted, forfeited, and expired during the year, and the tabular disclosure of the number of restricted stock units, restricted stock awards and performance stock awards that were outstanding at the beginning and end of the year and the number of restricted stock units, restricted stock awards and performance stock awards that were granted, exercised or converted, forfeited and expired during the year. + References No definition available. + Details
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- Definition Tabular disclosure of awards granted by fiscal year that includes the weighted-average grant date fair value and the number of unissued awards at the latest balance sheet date. + References No definition available. + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans, including, but not limited to: (a) expected term, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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