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Leases - Summary of Operating Lease Commitments Including Expected Lease Incentives to be Received (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Leases [Abstract]
2021 (remaining three months)	$ 2,419
2022	10,698
2023	11,018
2024	11,347
2025	11,859
Thereafter	60,302
Total undiscounted lease payments	107,643
Less: imputed interest	(33,422)
Less: tenant improvement allowances	(6,993)
Total operating lease liabilities	67,228
Operating Lease, Liability [Abstract]
Operating lease liabilities, non-current	65,684	$ 50,957
Total	67,228
Accrued Liabilities and Other Current Liabilities [Member]
Operating Lease, Liability [Abstract]
Short-term portion of lease liabilities (included in accrued liabilities and other current liabilities)	$ 1,544

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Lessee Operating Lease Liability Payments Due After Year Four

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LesseeOperatingLeaseLiabilityTenantImprovementAllowance

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- Definition

Amount of lessee's undiscounted obligation for lease payment 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=123408670&loc=SL77918701-209980

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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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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).

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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).

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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).

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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.

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

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

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

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

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