Loan Payable - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
Mar. 31, 2016	Apr. 30, 2013	Mar. 31, 2016
Debt Instrument [Line Items]
Term of warrant	5 years
Silicon Valley Bank Loan Agreement Warrant [Member]
Debt Instrument [Line Items]
Term of warrant			10 years
Exercise price of warrants	$ 20.4408		$ 20.4408
Warrant expiration period			2023-04
Silicon Valley Bank Loan Agreement Warrant [Member] \| Common Stock [Member]
Debt Instrument [Line Items]
Number of shares of common stock acquired using warrant	24,461		24,461
Silicon Valley Bank Loan Agreement [Member]
Debt Instrument [Line Items]
Proceeds from loan		$ 9,900,000
Cash discount	$ 100,000	$ 100,000	$ 100,000
Loan term			3 years
Annual interest rate on loan	6.00%		6.00%
Period of loan subject to interest payments only			6 months
Period of loan subject to principal and interest payments			30 months
Final fee payment at the end of loan term			$ 1,000,000
Proceeds received under loan agreement			9,900,000
Initial carrying amount assigned to loan, net of discount	$ 9,512,000		9,512,000
Fair value allocated to warrant	388,000		388,000
Note issuance costs			$ 117,000
Deferred financing costs, discount and accretion percentage			9.00%
Silicon Valley Bank Loan Agreement [Member] \| Restricted Money Market Account [Member]
Debt Instrument [Line Items]
Debt instrument, collateral amount	$ 2,422,500		$ 2,422,500

Carrying Value Of Purchased Loans

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Class Of Warrant Or Right Exercise Period Of Warrants Or Rights

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Class of Warrants Expiration Month and Year

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Debt Instrument Amortized Discount Percentage

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- Definition

Debt Instrument Period During Which Loan Is Subject To Interest Only Payments

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Debt Instrument Period During Which Loan Is Subject To Principal And Interest Payments

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Fair Value Allocated To Warrant

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Loan Fees

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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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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Amount of assets pledged to secure a debt instrument.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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- Definition

The net amount paid or received by the reporting entity associated with purchase (sale or collection) of loans receivable arising from the financing of goods and services.

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Cash received from principal payments made on loans related to operating activities.

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