Notes Payable - Schedule of Notes Payable (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Note payable	$ 15,000
Less: current portion	(1,475)
Note payable, net of current portion	13,525
Debt discount, net of accretion	(255)
Accretion related to final payment	249
Note payable, net of discount and current portion	$ 13,519	$ 14,873

Accretion related to final payment on notes payable.

No definition available.

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- Definition

Notes payable, net of current portion.

+ References

No definition available.

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- References

No definition available.

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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 of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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- Definition

Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

+ References

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