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- Definition

Debt Instrument, Covenant, Prepayment Feature, Use of Asset Proceeds, Minimum Amount

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- Definition

Debt Instrument, Covenant Terms, Unrestricted Cash Balance Requirement, Minimum

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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

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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- Definition

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

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- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

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- Definition

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

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- Definition

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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- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

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

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- Definition

The cash inflow from the additional capital contribution to the entity.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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- Definition

Value of preferred stock and warrants for common stock issued.

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Debt - Additional Information (Detail) - USD ($)			9 Months Ended	12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Dec. 19, 2014	Nov. 15, 2013	Dec. 31, 2015	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Mar. 16, 2017	Nov. 01, 2016	Apr. 30, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Amortization of debt discount				$ 156,000	$ 359,000	$ 566,000
Maturity date description				As a result of the Company’s April 2015 equity offering, the Minimum Threshold was reduced to the lesser of $2.0 million or the aggregate outstanding principal balance of the then outstanding term loans.
Term debt \| Hercules Technology Growth Capital \| FIrst warrants
Debt Instrument [Line Items]
Number of shares received from warrants received to purchase common stock (in shares)	13,927
Fair value of warrants issued	$ 400,000
Term debt \| Hercules Technology Growth Capital \| Second warrants
Debt Instrument [Line Items]
Number of shares received from warrants received to purchase common stock (in shares)	25,641
Fair value of warrants issued	$ 200,000
Term debt \| Hercules Technology Growth Capital \| Hercules warrants
Debt Instrument [Line Items]
Number of shares received from warrants received to purchase common stock (in shares)	58,823
Exercise price (in dollars per share)	$ 11.00			$ 9.38
Term loan B \| Term debt \| Hercules Technology Growth Capital
Debt Instrument [Line Items]
Debt, face amount		$ 10,000,000.0
Net proceeds from debt		$ 9,800,000
Interest rate on loan		11.00%
Debt fee amount								$ 500,000
Legal and origination costs recorded as debt discount											$ 200,000
Term loan B \| Term debt \| Hercules Technology Growth Capital \| Hercules warrants
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs, net	$ 1,000,000
Amortization of debt discount				$ 100,000	200,000
Term loan B \| Term debt \| Hercules Technology Growth Capital \| Prime rate
Debt Instrument [Line Items]
Basis spread that exceeds prime rate, percentage		3.75%
Term loan C \| Term debt \| Hercules Technology Growth Capital
Debt Instrument [Line Items]
Debt, face amount	1,500,000.0
Net proceeds from debt	$ 1,400,000
Interest rate on loan							11.25%
Debt fee amount				100,000
Legal and origination costs recorded as debt discount										$ 100,000
Prepayment feature, use of asset proceeds minimum				1,000,000
Proceeds from additional equity offering			$ 10,000,000
Term loan C \| Term debt \| Hercules Technology Growth Capital \| Hercules warrants
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs, net				300,000
Amortization of debt discount				100,000	100,000
Term loan
Debt Instrument [Line Items]
Amortization of debt discount				200,000	400,000	500,000
Interest expense, debt				400,000	$ 1,000,000	$ 1,700,000
Term loan \| Term debt \| Hercules Technology Growth Capital
Debt Instrument [Line Items]
Covenant terms, unrestricted cash balance requirement, minimum				$ 1,500,000.0
Maximum \| Term loan \| Term debt \| Hercules Technology Growth Capital
Debt Instrument [Line Items]
Covenant terms, unrestricted cash balance requirement, minimum									$ 2,000,000.0