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

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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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The number of new shares issued in the conversion of stock 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.

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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 of the cost of borrowed funds accounted for as interest expense for debt.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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The cash outflow for loan origination associated cost which is usually collected through escrow.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Fair value portion of warrants not settleable in cash classified as equity.

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Debt - Additional Information (Detail) - USD ($)		1 Months Ended		12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Aug. 04, 2016	Jul. 31, 2016	May 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Repayment of principal and accrued interest				$ 4,500,000
Warrant exercise price per share				$ 3.29	$ 16.73
Loan and security agreement [Member]
Debt Instrument [Line Items]
Loan and security agreement, interest incurred				$ 148,500	$ 250,938
Square 1 Bank [Member] \| Loan and security agreement [Member]
Debt Instrument [Line Items]
Loan and security agreement, available credit			$ 4,500,000
Loan and security agreement, amount drawn						$ 4,500,000
Fixed interest rate						5.50%
Repayment of principal and accrued interest	$ 4,500,000
Line of credit facility, loan origination cost			$ 82,685
Debt instrument, unamortized discount	38,000
Warrants exercisable, stock issued						22,881
Warrant exercise price per share						$ 5.90
Square 1 Bank [Member] \| Loan and security agreement [Member] \| Warrants to purchase common stock [Member]
Debt Instrument [Line Items]
Debt instrument, unamortized discount	$ 59,000
Common stock shares issued upon conversion of warrants		9,887
Warrant value recorded in equity						$ 108,122