The number of each class of warrants or rights exercised during the period.

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- Definition

Class of warrant or right, number of warrants available for cancellation.

+ References

No definition available.

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- Definition

Debt instrument maturity period.

+ References

No definition available.

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- Definition

Warrant exercisible term.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Face amount or stated value per share of common stock.

+ References

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

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-Topic 230
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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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- Definition

The cash inflow from issuance of callable preferred stock which is identified as being convertible to another type of financial security at the option of the issuer or the holder.

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

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Subsequent Events - Additional Information (Details) - USD ($)		1 Months Ended	3 Months Ended
	Jul. 11, 2019	May 23, 2019	Mar. 31, 2019	Jun. 06, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Debt instrument, principal face amount			$ 6,100,000		$ 4,500,000
Preferred stock, par value (in dollars per share)			$ 0.01		$ 0.01
Common stock, par value (in dollars per share)			0.01		0.01
warrant ,exercise price			$ 0.23		$ 0.22
Warrants exercised			4,119,500
Pre-Funded Series D Warrants [Member]
Subsequent Event [Line Items]
Warrants exercised			3,800,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Aggregate borrowed amount		$ 3,300,000
Debt instrument, principal face amount		$ 3,300,000		$ 2,000,000
Interest rate on promissory note		8.00%		8.00%
Maturity period		6 months
Subsequent Event [Member] \| Roth Capital Partners, LLC [Member]
Subsequent Event [Line Items]
Payments to private placement agent	$ 552,000
Subsequent Event [Member] \| Series E Convertible Preferred Stock [Member] \| Private Placement [Member] \| Scenario Plan [Member]
Subsequent Event [Line Items]
Expected proceeds from private placement, gross	20,000,000
Subsequent Event [Member] \| Series E Convertible Preferred Stock [Member] \| Private Placement [Member] \| Roth Capital Partners, LLC [Member] \| Scenario Plan [Member]
Subsequent Event [Line Items]
Payments to private placement agent	$ 1,400,000
Subsequent Event [Member] \| Series E Convertible Preferred Stock [Member] \| Private Placement [Member] \| Securities Purchase Agreement [Member]
Subsequent Event [Line Items]
Number of shares issued	20,000
Preferred stock, par value (in dollars per share)	$ 0.01
Shares issued, price per share	1,000
Subsequent Event [Member] \| Series D Warrants [Member]
Subsequent Event [Line Items]
Number of warrants available for cancellation				3,900,000
Subsequent Event [Member] \| Pre-Funded Series D Warrants [Member]
Subsequent Event [Line Items]
Number of warrants available for cancellation				53,400,000
Subsequent Event [Member] \| Warrants
Subsequent Event [Line Items]
warrant ,exercise price	$ 0.06
Warrant exercisible term	5 years
Subsequent Event [Member] \| Warrants \| Securities Purchase Agreement [Member]
Subsequent Event [Line Items]
Common stock, par value (in dollars per share)	$ 0.01