Leases - Summary of Maturities of Operating Lease Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
2019 (six months ended)	$ 4,417
2020	9,690
2021	12,671
2022	13,087
2023	13,515
2024	13,956
2025 and thereafter	78,233
Total lease payments	145,569
Less: portion representing interest	(43,021)
Less: lease incentives	(3,977)
Operating lease liabilities	98,571	$ 96,200
Less: current portion	(3,749)		$ 0
Operating lease liabilities, less current portion	$ 94,822		$ 0

Lessee operating lease liability payments due after year six.

No definition available.

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- Definition

Lessee operating lease liability payments due year six.

+ References

No definition available.

+ Details

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- Definition

Lessee operating lease liability tenant improvement reimbursements.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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