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Debt - Additional Information (Detail) - USD ($)				3 Months Ended
	Apr. 29, 2015	Dec. 19, 2014	Nov. 15, 2013	Jun. 30, 2016	Jun. 30, 2015
Debt Instrument [Line Items]
Proceeds from additional equity offering (more than)	$ 22,300,000
Non-cash interest expense amortization of debt discount (lless than $0.1 million each for Term Loan B and Term Loan C)				$ 100,000	$ 100,000
Interest expense, debt				200,000	300,000
FIrst Warrants | Senior Secured Loan | Hercules Technology Growth Capital
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
Second Warrants | Senior Secured Loan | Hercules Technology Growth Capital
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
Hercules Warrants | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Number of shares received from warrants received to purchase common stock (in shares)		58,823
Warrant exercise price (in dollars per share)	$ 9.41	$ 11.00
Term Loan B | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Debt, face amount			$ 10,000,000.0
Net proceeds from debt			$ 9,800,000
Interest rate, stated percentage			11.00%
Outstanding principal balance				1,700,000
End of term fee				500,000
Minimum amount of proceeds from specified asset dispositions for mandatory prepayment feature				1,000,000
Debt discount			$ 200,000
Term Loan B | Hercules Warrants | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Unamortized discount (premium) and debt issuance costs		$ 1,000,000
Non-cash interest expense amortization of debt discount (lless than $0.1 million each for Term Loan B and Term Loan C)				100,000	100,000
Term Loan C | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Debt, face amount		1,500,000.0
Net proceeds from debt		$ 1,400,000
Interest rate, stated percentage		11.00%
End of term fee				$ 100,000
Debt discount			$ 100,000
Debt instrument, maturity date				Jun. 01, 2017
Proceeds from additional equity offering (more than)				$ 10,000,000
Term Loan C | Hercules Warrants | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Unamortized discount (premium) and debt issuance costs		$ 300,000
Non-cash interest expense amortization of debt discount (lless than $0.1 million each for Term Loan B and Term Loan C)				100,000	$ 100,000
Term Loan | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Covenant, unrestricted cash balance requirement				$ 2,000,000
Prime Rate | Term Loan B | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Debt instrument, basis spread on prime rate			3.75%
Prime Rate | Term Loan C | Senior Secured Loan | Hercules Technology Growth Capital
Debt Instrument [Line Items]
Debt instrument, basis spread on prime rate		3.75%

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Debt Instrument, Covenant Terms, Unrestricted Cash Balance Requirement

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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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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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Percentage points added to the reference rate to compute the variable rate on 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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

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