Commitments and Contingencies - Supplemental Cash Flow Information Related to Operating Leases (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Cash payments for operating leases	$ 734
Right-of-use assets obtained in exchange for operating lease obligations	$ 13,560
Weighted-average remaining lease term	9 years 10 months 24 days
Weighted-average discount rate	9.00%

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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