Notes Payable - Schedule of Notes Payable (Detail) $ in Thousands	Sep. 30, 2018 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Roll Forward
Notes payable	$ 15,000
Notes payable, net of current portion	15,000
Debt discount, net of accretion	(331)
Accretion related to final payment	83
Notes payable net of discount, long-term	$ 14,752

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.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

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-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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