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Stockholders' Equity - Additional Information (Detail) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
Apr. 29, 2015 | Mar. 31, 2016 | Mar. 31, 2015 | Mar. 31, 2014 | Nov. 13, 2014
Stockholders Equity [Line Items] |  |  |  |  |
Weighted-average grant-date fair value of stock options granted |  |  | $ 10.18 | $ 16.20 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value |  | $ 0 | $ 0 | $ 0 |
Shares, Granted |  | 420,189 |  |  |
Number of shares cancelled |  | 14,949 |  |  |
Stock-based compensation plans expired terms |  | May 02, 2007 |  |  |
Contractual life of options, in years |  | 10 years |  |  |
Vesting period of shares granted by option upon election to board |  | 2 years |  |  |
Compensation expense recognized |  |  | $ 100,000 | 100,000 |
Common stock, shares issued |  | 14,107,126 | 9,624,275 |  |
Sale of stock, price per share |  |  |  |  | $ 11.00
Proceeds From Issuance Of Common Stock | $ 22,300,000 |  |  |  |
Cowen and Company, LLC |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Common stock, shares issued | 4,000,000 |  |  |  |
Sale of stock, price per share | $ 6.00 |  |  |  |
Proceeds From Issuance Of Common Stock | $ 22,300,000 |  |  |  |
Maximum |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Compensation expense recognized |  | $ 100,000 |  |  |
Stock Options |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures |  | $ 600,000 |  |  |
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years) |  | 2 years 4 months 24 days |  |  |
Stock options granted in period |  | 0 |  |  |
Stock Options | Minimum |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Vesting period, in years |  | 3 years |  |  |
Stock Options | Maximum |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Vesting period, in years |  | 5 years |  |  |
Restricted Stock and Stock Awards |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures |  | $ 2,600,000 |  |  |
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years) |  | 1 year 9 months 18 days |  |  |
Total fair value of restricted stock granted |  | $ 2,600,000 | $ 5,600,000 | 4,500,000 |
Total fair value of restricted stock granted for bonuses and severance |  |  |  | 500,000 |
Total fair value of restricted stock vested |  | $ 1,700,000 | $ 3,100,000 | 3,700,000 |
Total fair value of restricted stock granted for bonuses and severance |  |  |  | $ 500,000 |
Vesting period, in years |  | 3 years |  |  |
Performance-Based Restricted Stock |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Shares, Granted |  | 0 | 38,021 | 40,201 |
Restricted Stock Units (RSUs) |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Number of shares cancelled |  | 6,666 |  |  |
2007 Director Stock Option Plan |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Number of shares granted by option upon election to the board |  | 1,000 |  |  |
Number of shares awarded annually |  | 300 |  |  |
Grant date value of shares granted by option upon election to board |  | $ 40,000 |  |  |
Number of shares authorized for issuance under the plan |  | 35,505 |  |  |
2007 Stock Incentive Plan |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Number of shares authorized for issuance under the plan |  | 195,194 |  |  |
Employee Stock Purchase Plan |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |
Number of shares authorized for issuance under the plan |  | 0 |  |  |
Percentage of purchase discount |  | 15.00% |  |  |

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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