Additional issuance of Common stock purchase price per share.

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Amortization payments number of equal installments.

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Debt conversion converted instrument put options issued on default and change in control, value.

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Period after original date of issuance of debt instrument for which amortization payment begins.

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Proceeds from issuance of notes and warrants.

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Proceeds from issuance of notes available for use.

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Rate of interest in event of default.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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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

Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date.

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The price per share of the conversion feature embedded in the debt instrument.

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- Definition

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

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

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Date the debt instrument was issued, in CCYY-MM-DD format.

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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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Amount, after accumulated amortization, of debt discount.

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Amount, before accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of expense (income) related to adjustment to fair value of warrant liability.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The aggregate amount paid by the entity to reacquire the right to purchase equity shares at a predetermined price, usually issued together with corporate debt.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Convertible Notes Payable - Additional Information (Details) $ / shares in Units, shares in Millions				1 Months Ended	3 Months Ended			6 Months Ended
	Apr. 02, 2017 USD ($)	Jun. 13, 2016	Jun. 06, 2016 USD ($) Installment $ / shares shares	Dec. 31, 2016 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	May 09, 2017 $ / shares	Apr. 10, 2017 $ / shares	Mar. 13, 2017 $ / shares	Mar. 02, 2017 $ / shares	Feb. 10, 2017 $ / shares	Feb. 01, 2017 $ / shares	Jan. 12, 2017 $ / shares
Debt Instrument [Line Items]
Gain on warrant extinguishment					$ 9,613,000		$ 0	$ 9,613,000	$ 0
Warrant liability fair value adjustment					38,000		1,181,000	(1,200,000)	(491,000)
Debt instrument, conversion price \| $ / shares										$ 0.05	$ 0.06	$ 0.11	$ 0.14	$ 0.20	$ 0.32	$ 0.36
Securities Purchase Agreement [Member] \| Warrant Repurchase Agreements [Member]
Debt Instrument [Line Items]
Aggregate amount to be paid in exchange for cancellation of warrants	$ 7,900,000
Gain on warrant extinguishment	9,600,000
Warrant liability fair value adjustment	$ 17,500,000
Senior Secured Convertible Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal face amount					18,853,000		$ 35,000,000	18,853,000	35,000,000
Debt discount on senior notes					6,256,000			6,256,000
Senior Secured Convertible Notes [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Debt instrument, principal face amount			$ 35,000,000
Debt discount on senior notes			2,800,000		$ 35,000,000			$ 35,000,000
Interest rate upon default					0.00%			0.00%
Rate of interest in event of default								15.00%
Debt instrument interest rate computation terms								The Notes do not bear any ordinary interest. However, interest shall commence accruing immediately upon the occurrence of, and shall continue accruing during the continuance of, an Event of Default, at 15% per annum and shall be computed on the basis of a 360-day year of twelve 30-day months and shall be payable
Proceeds from issuance of notes available for general corporate purposes			$ 3,000,000	$ 3,000,000		$ 6,600,000
Cash held in the restricted accounts					$ 11,800,000			$ 11,800,000
Amortization payments number of equal installments \| Installment			14
Period after original date of issuance of notes for which amortization payment begins		7 months
Debt instrument, original issuance date								Jun. 13, 2016
Debt instrument, conversion price \| $ / shares			$ 4.39
Debt discount amortization								$ 28,700,000
Beneficial conversion feature								4,400,000
Debt instrument, put options issued on default and change in control, value					0			0
Debt issuance costs					$ 1,600,000			1,600,000
Amortization of debt issuance costs								800,000
Senior Secured Convertible Notes [Member] \| Securities Purchase Agreement [Member] \| Restricted Cash [Member]
Debt Instrument [Line Items]
Proceeds from issuance of notes and warrants								11,800,000
Series C Warrants [Member]
Debt Instrument [Line Items]
Aggregate amount to be paid in exchange for cancellation of warrants								$ 7,876,000	$ 0
Series C Warrants [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Additional issuance of common stock purchase price per share. \| $ / shares			$ 0.01
Series C Warrants [Member] \| Senior Secured Convertible Notes [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Proceeds from issuance of notes and warrants			$ 32,200,000
Debt discount on senior notes			$ 27,800,000
Shares issuable upon warrants exercised \| shares			6.8