Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Indicates (true false) whether lessee has option to extend operating lease.

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

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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).

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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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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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Amount of monetary allowance granted by the landlord to a tenant for operating lease.

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Represents the number of phases associated with a lease term.

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Leases (Details) $ in Thousands	1 Months Ended		3 Months Ended	6 Months Ended
Leases (Details) $ in Thousands	Jun. 30, 2021 item	Jul. 31, 2017	Jun. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2026 USD ($)	Aug. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Option to extend		true
ROU assets exchanged for operating lease liabilities			$ 1,500	$ 1,500
For the remainder of 2022			1,064	1,064
2023			6,804	6,804
2024			5,713	5,713
2025			5,817	5,817
2026			5,279	5,279
2027			5,433	5,433
Thereafter			46,685	46,685
Total undiscounted lease payments			76,795	76,795
Less: Tenant allowance			(10,817)	(10,817)
Less: Imputed interest			(24,388)	(24,388)
Present value of lease payments			41,590	41,590
Lease liability - long-term			$ 33,943	$ 33,943			$ 33,969
Monrovia, CA - office and laboratory space
Lessee, Lease, Description [Line Items]
Renewal term			5 years	5 years
Monrovia, CA - office and laboratory space with additional space
Lessee, Lease, Description [Line Items]
Renewal term			2 years	2 years
Pasadena, CA - office and laboratory space
Lessee, Lease, Description [Line Items]
Phases of lease term \| item	2
Forecast \| Pasadena, CA - office and laboratory space
Lessee, Lease, Description [Line Items]
Improvement allowance					$ 3,300	$ 17,000