Class of Warrant or Right, Purchase Price of Warrants or Rights.

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- Definition

Employee stock purchase plan offering period.

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- Definition

Number of equity incentive plans.

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Number of warrants expired.

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Date the warrants or rights are exercisable, in CCYY-MM-DD format.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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No definition available.

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Number of warrants or rights outstanding.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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.

+ References

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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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

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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No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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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.

+ References

No definition available.

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Number of options outstanding, including both vested and non-vested options.

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Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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Percentage of vesting of share-based compensation awards.

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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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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock-Based Compensation and Warrants - Additional Information (Detail)				1 Months Ended	3 Months Ended
	Mar. 28, 2019 shares	May 20, 2015 shares	May 14, 2015	Dec. 31, 2013 $ / shares shares	Jun. 30, 2019 shares	Mar. 31, 2019 USD ($) IncentivePlan $ / shares shares	Sep. 30, 2018	Mar. 31, 2018 USD ($) shares	Dec. 31, 2018 shares	Jun. 30, 2014 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| IncentivePlan						2
Total number of options outstanding						535,243			530,044
Unrecognized compensation cost related to unvested stock-based compensation grants \| $						$ 900,000
Weighted-average remaining recognition period						1 year 10 months 24 days
Options granted						7,500		10,000
Stock-based compensation \| $						$ 422,000		$ 298,000
Number of warrant to purchase common stock issued						2,821,144
Warrants issued, exercise price \| $ / shares						$ 18.15
March 2018 Purchase Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrant to purchase common stock issued						1,297,870
Warrants issued, exercise price \| $ / shares						$ 10.7258
Series D Redeemable Convertible Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants issued, exercise price \| $ / shares										$ 363.20
Warrant issued, shares of common stock called by warrant										61,397
Number of warrants expired	1,759
Series D Redeemable Convertible Preferred Stock [Member] \| Scenario Forecast [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants expired					59,638
Series D Redeemable Convertible Preferred Stock [Member] \| Placement Agent [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants issued, exercise price \| $ / shares										$ 268.80
Warrant issued, shares of common stock called by warrant										1,674
Mahyco International [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants issued, exercise price \| $ / shares				$ 330.40
Warrant issued, shares of common stock called by warrant				3,784
Warrant, expiration date				Dec. 11, 2018
2015 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of shares reserved for issuance under plan						108,864
Percentage in payroll deductions to acquire shares of common stock			15.00%
Purchase plan offering period			6 months
Employees are able to purchase company's common stock on first trading day of offering period, percentage			85.00%
Issuance of common stock pursuant to employee stock purchase plan						9,353
Stock-based compensation \| $						$ 4,300		$ 1,200
Purchase Agreement [Member] \| June 2018 Offering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrant to purchase common stock issued						1,461,962
Purchase Agreement [Member] \| June 2018 Offering [Member] \| Purchase Price of $9.94 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrant to purchase common stock issued						1,392,345
Warrants issued, purchase price of warrants per share \| $ / shares						$ 9.94
Purchase Agreement [Member] \| June 2018 Offering [Member] \| Exercise Price of $12.568 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrant to purchase common stock issued						69,617
Warrants issued, exercise price \| $ / shares						$ 12.568
2015 Omnibus Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Terms under the plan						The 2015 Plan became effective in May 2015 and all shares that were reserved, but not issued, under the 2006 Plan were assumed by the 2015 Plan. Upon effectiveness, the 2015 Plan had 154,387 shares of common stock reserved for future issuance, which included 10,637 shares under the 2006 Plan that were transferred to and assumed by the 2015 Plan. The 2015 Plan provides for automatic annual increases in shares available for grant. In addition, shares subject to awards under the 2006 Plan that are forfeited or canceled will be added to the 2015 Plan.
Total number of shares reserved for issuance under plan		154,387				538,953
Options vesting period		4 years					2 years
Common stock available for future grant						65,872
Total number of options outstanding						473,081
2015 Omnibus Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable period		10 years
2015 Omnibus Equity Incentive Plan [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting percentage at end of one year		25.00%
2006 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of shares reserved for issuance under plan		10,637
Total number of options outstanding						62,162