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Number of shares granted by option upon election to the board.

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Number of warrants issued to purchase common stock.

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Percentage on sale of stock consideration received on transaction.

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Share-based compensation arrangement by share-based payment award, equity instruments other than options, bonus and severance grants, fair value.

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Share-based compensation arrangement by share-based payment award, equity instruments other than options, bonus and severance stock vested in period, fair value.

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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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Number of shares awarded annually under the share-based compensating arrangement.

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Share-based compensation arrangement by share-based payment award options contractual life.

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Vesting period of shares granted by option upon election to board.

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Warrants to purchase one share of common stock.

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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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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Number of common units issued of limited liability company (LLC).

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Unrecognized cost of unvested share-based compensation awards.

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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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The amount of plan compensation cost recognized during the period.

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

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

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

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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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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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Date the equity-based award expires, in CCYY-MM-DD format.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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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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Number of share instruments newly issued under a share-based compensation plan.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Stockholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended		12 Months Ended
	Mar. 24, 2015	Nov. 13, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Nov. 15, 2013
Stockholders Equity [Line Items]
Weighted-average grant-date fair value of stock option awards granted			$ 10.18	$ 16.20	$ 25.60
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value			$ 0	$ 0	$ 0
Shares, Granted			332,782
Number of shares cancelled			22,788
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	100,000
Common stock			96,000us-gaap_CommonStockValue	79,000us-gaap_CommonStockValue
Proceeds From Issuance Of Common Stock		9,100,000
Common stock, shares issued			9,624,275us-gaap_CommonStockSharesIssued	7,892,990us-gaap_CommonStockSharesIssued
Shares issued, price per share		$ 11.00us-gaap_SaleOfStockPricePerShare
Reverse stock split, description			adjusted to reflect our 1-for-10 reverse stock split
Reverse stock split	0.1	0.1
Common stock units offered		909,090us-gaap_CommonUnitIssued
Number of warrants issued to purchase common stock		818,181
Warrants to purchase one share of common stock		90.00%
M L V And Co \| At Market Sales Agreement
Stockholders Equity [Line Items]
Commission on sale of common stock under the ATM						3.00%
M L V And Co \| Atm Arrangement
Stockholders Equity [Line Items]
Proceeds From Issuance Of Common Stock			5,800,000	7,500,000
Common stock, shares issued			375,000	487,000
Shares issued, price per share			$ 16.05	$ 16.24
Maximum \| M L V And Co \| At Market Sales Agreement
Stockholders Equity [Line Items]
Common stock						30,000,000
Stock Options
Stockholders Equity [Line Items]
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures			1,200,000	2,000,000
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)			2 years 8 months 12 days
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	1,800,000
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)			1 year 2 months 12 days
Total fair value of restricted stock granted			5,600,000	4,500,000	10,600,000
Total fair value of restricted stock granted for bonuses and severance				500,000	1,600,000
Total fair value of restricted stock vested			3,100,000	3,700,000	3,400,000
Total fair value of restricted stock granted for bonuses and severance				500,000	1,600,000
Vesting period, in years			3 years
U.S. Treasury Rates \| Minimum
Stockholders Equity [Line Items]
Stock-based compensation plans expired terms			5 years
U.S. Treasury Rates \| Maximum
Stockholders Equity [Line Items]
Stock-based compensation plans expired terms			7 years
Performance-Based Restricted Stock
Stockholders Equity [Line Items]
Shares, Granted			38,021	40,201	142,212
Restricted Stock Units (RSUs)
Stockholders Equity [Line Items]
Number of shares cancelled			10,000
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			64,700
2007 Stock Incentive Plan
Stockholders Equity [Line Items]
Number of shares authorized for issuance under the plan			557,578
Employee Stock Purchase Plan
Stockholders Equity [Line Items]
Number of shares authorized for issuance under the plan			16,708
Percentage of purchase discount			15.00%
Common stock shares issued			8,168