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Proceeds from Issuance At-the-market Offering

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Sale of Stock, Value, Shares Authorized for Sale

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Share Based Compensation Arrangement By Share Based Payment Award Options Contractual Life

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants In Period, Fair Value

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The cash inflow from the additional capital contribution to the entity.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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).

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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.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Stockholders' Equity - Additional Information (Detail) - USD ($)		12 Months Ended
	Apr. 29, 2015	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Jan. 27, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period (in shares)		9,703	0
Weighted-average grant-date fair value of stock options granted (in dollars per share)		$ 4.06	$ 10.18
Intrinsic value of exercisable options		$ 0	$ 0	$ 0
Granted (in shares)		171,000
Number of shares cancelled (in shares)		0
Stock-based compensation expense (less than $0.1 million in 2016)		$ 2,892,000	$ 3,248,000	5,936,000
Common stock, shares issued (in shares)		14,713,839	14,107,126
Proceeds from sale of stock		$ 2,527,000	$ 0	5,839,000
Cowen and Company, LLC
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued (in shares)	4,000,000
Sale of stock, price per share (in dollars per share)	$ 6.00
Proceeds from additional equity offering	$ 22,300,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures		$ 400,000
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)		1 year 10 months 24 days
Stock-based compensation expense (less than $0.1 million in 2016)		$ 323,000	663,000	1,851,000
Restricted stock and stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted stock granted		1,700,000	2,600,000	5,600,000
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures		$ 1,800,000
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)		1 year 3 months 18 days
Total fair value of restricted stock vested		$ 2,300,000	1,700,000	3,100,000
Stock-based compensation expense (less than $0.1 million in 2016)		$ 2,569,000	$ 2,574,000	$ 4,063,000
Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		0	0	38,021
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares cancelled (in shares)		3,333
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance under the plan (in shares)		300,013
Percentage of purchase discount		15.00%
Stock-based compensation expense (less than $0.1 million in 2016)		$ 0	$ 11,000	$ 22,000
ATM arrangement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of stock, price per share (in dollars per share)		$ 6.79
Sale of stock					$ 10,000,000.0
Number of shares sold (in shares)		379,693
2007 Director stock option plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, in years		2 years
Grant date value of shares granted by option upon election to board		$ 40,000
Total fair value of restricted stock granted		$ 40,000
Number of shares authorized for issuance under the plan (in shares)		150,802
2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life of options, in years		10 years
Vesting period, in years		3 years
Number of shares authorized for issuance under the plan (in shares)		1,405,110
2007 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, in years		3 years
2007 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, in years		5 years