Debt Instrument Number Of Periodic Payments

No definition available.

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- Definition

Debt instrument prepayment date.

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility Prepayment Charges, Percentage

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Maximum Amount Of Convertible Debt

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Discussion of the facts and amounts pertaining to each failure to comply with an affirmative or negative covenant of a long-term debt instrument, including violating payment terms or an inability to meet certain minimum financial requirements or achieve or maintain certain financial ratios. The discussion would generally be expected to also include whether or not the failure can and will be overcome and a description of the terms of any waivers, including the amount of the waiver and the period of time covered by the waiver, and if reclassification of long-term debt to current has been made in the current balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6802200&loc=SL6230698-112601

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(c))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph c
-Article 4

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.9)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 9
-Article 9

+ Details

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Balance Type:	debit
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fee for available but unused credit capacity under the credit facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Increase for accrued, but unpaid interest on the credit facility for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph f
-Article 4

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Period Type:	duration

- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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- Definition

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.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Period Type:	instant

- Definition

The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Long-Term Obligations - Additional Information (Detail)					3 Months Ended		9 Months Ended		12 Months Ended
Long-Term Obligations - Additional Information (Detail)	Feb. 01, 2018 USD ($)	Aug. 03, 2015 USD ($)	Jun. 30, 2015 USD ($)	Aug. 01, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) Payments	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($) $ / shares	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Jul. 31, 2014 USD ($)
Debt Instrument [Line Items]
Loan fees							$ 1,750,000	$ 334,000	$ 387,000
Interest expense					$ 1,347,000	$ 271,000	$ 2,302,000	$ 330,000	$ 741,000	$ 59,000	$ 108,000
Convertible Debt [Member]
Debt Instrument [Line Items]
Interest expense										$ 100,000	$ 100,000
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Capital lease, number of payments \| Payments							60
Capital lease obligations							$ 600
Hercules Loan Agreement [Member]
Debt Instrument [Line Items]
Loan agreement, terms on interest rate calculation							The Loan accrued interest at a rate equal to the greater of either (i) 8.25% plus the prime rate as reported from time to time in The Wall Street Journal minus 5.25%, and (ii) 8.25%. Contractual payments under the Loan Agreement were interest only until August 1, 2015
Loan agreement, interest rate during the period					8.25%		8.25%
Loan agreement, milestone description							In April 2015, the Company's senior management and board of directors determined that the Company did not achieve the Milestone (see Note 7). Accordingly, the Company could not draw down the second tranche of $15.0 million.
Outstanding principal balance		$ 10,000,000
Accrued and unpaid interest		75,625
End of term charge		1,750,000
Debt instrument prepayment date							Aug. 03, 2015
Total payment of debt		$ 11,825,625
Hercules Loan Agreement [Member] \| Prime Rate [Member]
Debt Instrument [Line Items]
Loan agreement, percentage to be reduced from interest rate under condition							(5.25%)
Hercules Loan Agreement [Member] \| First Tranche [Member]
Debt Instrument [Line Items]
Loan agreement, maximum borrowing capacity												$ 25,000,000
Loan agreement, amount borrowed				$ 10,000,000
Hercules Loan Agreement [Member] \| Second Tranche [Member]
Debt Instrument [Line Items]
Loan agreement, amount borrowed			$ 15,000,000
Expiration date of tranche							Jun. 30, 2015
Scenario, Forecast [Member] \| Hercules Loan Agreement [Member]
Debt Instrument [Line Items]
Loan fees	$ 1,750,000
Hercules Technology III L.P. and Hercules Technology Growth Capital, Inc. [Member]
Debt Instrument [Line Items]
Loan agreement, terms on interest rate calculation									The interest rate for each tranche will be calculated at a rate equal to the greater of either (i) 8.25% plus the prime rate as reported from time to time in The Wall Street Journal minus 5.25%, and (ii) 8.25%. Payments under the Loan Agreement are interest only until August 1, 2015 (which will be extended until February 1, 2016 if the Company achieves the Milestone on or before June 30, 2015)
Loan agreement, interest rate during the period									8.25%
Prepayment charge									1.50%
Maximum convertible limit of principal installment									$ 3,000,000
Conversion price \| $ / shares									$ 16.33
Addition in interest rate on default									5.00%
Interest expense									$ 700,000
Hercules Technology III L.P. and Hercules Technology Growth Capital, Inc. [Member] \| Prime Rate [Member]
Debt Instrument [Line Items]
Loan agreement, percentage to be reduced from interest rate under condition									(5.25%)
Hercules Technology III L.P. and Hercules Technology Growth Capital, Inc. [Member] \| First Tranche [Member]
Debt Instrument [Line Items]
Loan agreement, maximum borrowing capacity												$ 25,000,000
Loan agreement, amount borrowed				10,000,000
Loan fees				150,000
Loan agreement, commitment fee paid				$ 37,500
Hercules Technology III L.P. and Hercules Technology Growth Capital, Inc. [Member] \| Second Tranche [Member]
Debt Instrument [Line Items]
Expiration date of tranche									Jun. 30, 2015
Hercules Technology III L.P. and Hercules Technology Growth Capital, Inc. [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Loan fees	$ 1,750,000
Hercules Technology III L.P. and Hercules Technology Growth Capital, Inc. [Member] \| Scenario, Forecast [Member] \| Second Tranche [Member]
Debt Instrument [Line Items]
Loan fees			100,000
Loan agreement, amount borrowed			$ 15,000,000