Offering period.

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- Definition

Purchase period.

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No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 235
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- Definition

Number of warrants or rights outstanding.

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- Definition

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

+ References

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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.

+ References

No definition available.

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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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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Number of share options (or share units) exercised during the current period.

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Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense capitalized as part of cost of inventory		$ 1.3			$ 1.3
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		229,911	1,294,053
Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares issued (in shares)		672,442	408,964
Contingent stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)			1,035,000
Common stock warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares issued (in shares)		2,320	18,285
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period		2 years
Purchase period		Four Six-Month
Purchase of common stock under ESPP (in shares)		0	0
First anniversary \| 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	25.00%
Monthly vesting over following 3 years \| 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		75.00%		75.00%
Series A warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding warrants (in shares)		415,200	492,500
Warrants exercise price (USD per share)		$ 3.50
Common Stock Warrant Expiring March 2027
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding warrants (in shares)		193,788
Warrants exercise price (USD per share)		$ 23.50
Common Stock Warrant Expiring Between August 2021 and August 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding warrants (in shares)		95,781
Warrants exercise price (USD per share)		$ 73.73