Purchase price per share or per unit of warrants outstanding.

No definition available.

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- Definition

Exercise price per share or per unit of warrants received as compensation.

+ References

No definition available.

+ Details

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- Definition

The number of new shares issued in the conversion of preferred stock received as compensation in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

No definition available.

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- Definition

The lock-up period for purchased shares by counterparty under agreement.

+ References

No definition available.

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- Definition

Represents information pertaining to period during which the underwriter's have an option to purchase additional shares.

+ References

No definition available.

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- Definition

The percentage of management fee on gross proceeds of the offering and other expenses.

+ References

No definition available.

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- Definition

The percentage of underwriters commission on gross proceeds of the offering.

+ References

No definition available.

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- Definition

Represents the percentage of public offering exercise price of warrants.

+ References

No definition available.

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- Definition

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

+ References

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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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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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-Publisher FASB
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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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- Definition

Number of new stock issued during the period.

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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.

+ Details

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Securities Registrations and Sales Agreements - underwriting agreement with HCW (Details) - USD ($) $ / shares in Units, $ in Millions								12 Months Ended
	May 01, 2018	Apr. 27, 2018	Apr. 16, 2018	Feb. 12, 2018	Feb. 08, 2018	Nov. 14, 2017	Apr. 26, 2017	Dec. 31, 2017	Dec. 31, 2018	Sep. 24, 2018	Jun. 07, 2018	Jun. 06, 2018	Mar. 21, 2018	Mar. 20, 2018
Subsidiary, Sale of Stock [Line Items]
Net proceeds from stock offering	$ 25.6			$ 8.7
Common Stock authorized (in shares)								25,000,000	250,000,000		250,000,000	100,000,000	100,000,000	25,000,000
Percentage of exercise price of warrants			105.00%
Common Stock
Subsidiary, Sale of Stock [Line Items]
Issuance of stock (in shares)								267,418
Pre-funded warrants
Subsidiary, Sale of Stock [Line Items]
Warrant exercise price (in dollars per share)		$ 0.15			$ 0.15
Preferred stock warrants \| Series A Convertible Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Warrant exercise price (in dollars per share)		$ 6.375
Preferred stock warrants \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Warrant exercise price (in dollars per share)	$ 6.69375				$ 15.15
HCW
Subsidiary, Sale of Stock [Line Items]
Underwriters commission (in percentage)		8.00%			7.00%
Management fee (in percentage)		1.00%			1.00%
HCW \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Number of common stock shares for conversion preferred stock received as compensation					33,158
HCW \| Preferred stock warrants \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Warrants exercise price received as compensation (in dollars per share)					$ 18.9375					$ 7.96875
The Offering
Subsidiary, Sale of Stock [Line Items]
Issuance of stock (in shares)						61,333	165,079
The Offering \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Issuance of stock (in shares)		3,105,882			380,500
Share price (in dollars per share)		$ 6.375			$ 15.15
The Offering \| Pre-funded warrants
Subsidiary, Sale of Stock [Line Items]
Warrant purchase price (in dollars per share)					$ 15.00
The Offering \| Pre-funded warrants \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Number of securities to each class of warrant (in shares)		815,686			196,167
Underwriter's option \| HCW
Subsidiary, Sale of Stock [Line Items]
Period available to underwriters to purchase additional shares under the offering					30 days
Underwriter's option \| HCW \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Issuance of stock (in shares)		588,235			86,500
Share price (in dollars per share)		$ 6.225			$ 15.00
Lock-up period for purchased shares by counterparty (in days)					135 days
Underwriter's option \| HCW \| Preferred stock warrants \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Number of securities to each class of warrant (in shares)		588,235			86,500
Warrant purchase price (in dollars per share)		$ 0.15			$ 0.15