Debt instrument, applicable interest rate is the the sum of base % plus the 30-day U.S. LIBOR rate.

No definition available.

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- Definition

Debt instrument, applicable interest rate scenario one.

+ References

No definition available.

+ Details

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- Definition

Debt instrument number of installments.

+ References

No definition available.

+ Details

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- Definition

Final payment fee percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

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- Definition

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

+ References

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+ Details

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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

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

+ References

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Period Type:	duration

- Definition

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

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+ Details

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Balance Type:	debit
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

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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- Details

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- Details

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Long-Term Debt - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) Installment	Sep. 30, 2017 USD ($)
Debt Instrument [Line Items]
Loan repayment terms			Payments on the notes payable will be interest only through May 2019, followed by 41 months of monthly payments of interest and principal.
Number of installments description			41 months of monthly payments of interest and principal
Number of installments \| Installment			41
Final payment fee percentage			6.50%
Debt instrument, applicable interest rate for scenario 1	8.05%		8.05%
Debt instrument, base interest rate for scenario 2	6.81%		6.81%
Interest rate description			The interest rate under the Amended Loan Agreement is the greater of (a) 8.05% or (b) the sum of 6.81% plus the 30-day U.S. LIBOR rate.
Interest expense	$ 867	$ 806	$ 2,628	$ 2,346
Loan and Security Agreement [Member]
Debt Instrument [Line Items]
Additional amount received on debt instrument			10,000
Oxford and Silicon Valley Bank [Member] \| Loan and Security Agreement [Member]
Debt Instrument [Line Items]
Additional amount received on debt instrument	10,000
Interest expense	$ 800	$ 800	$ 2,600	$ 2,300
Effective interest rate on the amounts borrowed under the Agreement	8.90%		8.90%