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Class of warrant or right, outstanding, buy back, description.

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Class of warrant or rights date from which warrants or rights exercisable, end date.

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Class of warrant or rights date from which warrants or rights exercisable, start date.

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Maximum required market price of common shares, to settle notes payable in cash.

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Proceeds from issuance of notes and warrants.

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Amount of amortization expense attributable to debt issuance costs.

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

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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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Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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

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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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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Secured Convertible Notes Payable and Common Stock Purchase Warrants - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions		3 Months Ended		6 Months Ended
	Jun. 04, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Debt Instrument [Line Items]
Loss on issuance of financial instrument		$ 2,826,000	$ 0	$ 2,826,000	$ 0
Series D Warrants [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Debt discount on senior notes	$ 2,300,000
Loss on issuance of financial instrument	$ 2,800,000
Series D-1 Warrants [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Shares issuable upon warrants exercised	1.1
Exercise price of warrants	$ 4.00
Warrants term	5 years
Series D-2 [101-113] Warrants [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Shares issuable upon warrants exercised	13.0
Exercise price of warrants	$ 0.01
Buy back of warrants, description				The Company may buy back each D-2 Warrant on its date of initial exercisability so long as the Company is not in default and the applicable installment payment for each month commencing on January 4, 2019 through December 4, 2019 has been paid when due.
Warrants term	5 years
Warrants exercisable, description				D-2 Warrants have a five-year term from initial exercisability which begins on the fifth day of each month commencing December 5, 2018, through December 5, 2019, for each of Warrant D-2-101 through 113 respectively.
Warrants exercisable, start date	Dec. 05, 2018
Warrants exercisable, end date	Dec. 05, 2019
Senior Secured Convertible Notes [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Interest rate	8.00%
Notes payable terms				The Notes bear 8% interest payable quarterly in cash. Of the $3.3 million in issued Notes, $2.5 million matures in six months; the balance of $0.8 million is payable in twelve installments beginning seven (7) months after the original issuance date.
Debt instrument, conversion price	$ 3.00
Maximum required market price of common shares, to settle notes payable in cash	$ 3.00
Senior Secured Convertible Notes [Member] \| Securities Purchase Agreement [Member] \| Matures in Six Months [Member]
Debt Instrument [Line Items]
Notes payable maturity amount	$ 2,500,000
Senior Secured Convertible Notes [Member] \| Securities Purchase Agreement [Member] \| Payable in Twelve Installments Beginning Seven Months After Original Issuance Date [Member]
Debt Instrument [Line Items]
Notes payable maturity amount	800,000
Senior Secured Convertible Notes [Member] \| Series D Warrants [Member]
Debt Instrument [Line Items]
Debt instrument, principal face amount	3,300,000
Senior Secured Convertible Notes [Member] \| Series D Warrants [Member] \| Securities Purchase Agreement [Member]
Debt Instrument [Line Items]
Proceeds from issuance of notes and warrants	2,400,000
Debt discount on senior notes	$ 1,100,000