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Long-Term Debt - Summary of Long Term Debt (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Long-term Debt, Unclassified [Abstract]
Principal amount of long-term debt	$ 19,546	$ 10,000
Less: Current portion of long-term debt	(5,298)	(1,687)
Long-term debt, net of current portion	14,248	8,313
Debt discount, net of accretion	(1,019)	(226)
Cumulative accretion of final payment due at maturity	136	58
Long-term debt, including accretion, net of current portion	$ 13,365	$ 8,145

X

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Name Accounting Standards Codification
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-SubTopic 30
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X

- Definition

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.

+ References

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- Definition

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

+ References

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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- Definition

Accretion On Long Term Debt

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No definition available.

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Long term debt non current including accretion.

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