Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Less: debt-current		$ (7,857)
Debt-non-current	$ 39,327	22,013
Term Loan Credit Agreement
Debt Instrument [Line Items]
Total debt, Principal	40,000
Total debt, Unamortized Discount	(673)
Total debt	39,327
Debt - non-current, Principal	40,000
Debt - non-current, Unamortized Discount	(673)
Debt-non-current	$ 39,327
Oxford Term Loan Agreement
Debt Instrument [Line Items]
Total debt, Principal		30,000
Total debt, Unamortized Discount		(130)
Total debt		29,870
Less: debt - current, Principal		(7,857)
Less: debt-current		(7,857)
Debt - non-current, Principal		22,143
Debt - non-current, Unamortized Discount		(130)
Debt-non-current		$ 22,013

Current portion carrying value of the debt instrument before deducting unamortized discounts (if any).

No definition available.

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- Definition

Non-current portion carrying value of the debt instrument before deducting unamortized discounts (if any).

+ References

No definition available.

+ Details

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- Definition

Non-current portion of the unamortized discounts on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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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.

+ References

No definition available.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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- Definition

Carrying value as of the balance sheet date of the portion of long-term, collateralized debt obligations due within one year or the operating cycle, if longer. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

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