Commitments and Contingencies - Schedule of Future Minimum Lease Commitments Under Non-cancelable Operating Leases and Scheduled Sublease Payments (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Gross Payments, 2019	$ 3,209
Gross Payments, Total future minimum lease payments	3,209
Scheduled Sublease Payments, 2019	2,119
Scheduled Sublease Payments, Total future minimum lease payments	2,119
Net Payments, 2019	1,090
Net Payments, Total future minimum lease payments	$ 1,090

Operating leases future minimum payments due future minimum gross payments due.

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Operating leases future minimum payments due future minimum gross payments due current.

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Operating leases future minimum payments future minimum sublease rentals due.

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Operating leases future minimum payments future minimum sublease rentals due current.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

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-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

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-Name Accounting Standards Codification
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-Section 55
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-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

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