Leases - Schedule of Undiscounted Future Lease Payments under Operating Lease (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Operating Leases
2021 (remaining 3 months)	$ 818
2022	6,049
2023	13,947
2024	14,405
2025	14,880
Thereafter	149,252
Total undiscounted lease payments	199,351
Less: Present value adjustment	(75,629)
Less: Tenant improvement allowance	(30,015)
Add: Lease incentive receivable	7,358	$ 0
Lease, liability	101,065
Sublease Payments Receivable
2021 (remaining 3 months)	463
2022	491
2023	5,844
2024	6,019
2025	6,200
Thereafter	89,136
Total undiscounted lease payments	$ 108,153

Lessee, Operating Lease, Liability, To Be Paid, After Year Four

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- Definition

Lessor, Operating Lease, Payment to be Received, after Year Four

+ References

No definition available.

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- Definition

Amount of incentive granted by lessor to lessee.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

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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.

+ References

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- References

No definition available.

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- Definition

Amount of lease payments to be received by lessor for operating lease.

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- Definition

Amount of lease payment to be received by lessor for operating lease in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lease payment to be received by lessor for operating lease in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lease payment to be received by lessor for operating lease in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lease payment to be received by lessor for operating lease in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- References

No definition available.

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- Definition

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

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-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

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-Name Accounting Standards Codification
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-Paragraph 1
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