Number of options to renew.

No definition available.

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- Definition

Proceeds from Tenant Improvement Allowance

+ References

No definition available.

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- Definition

Area of land subject to a ground lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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- Details

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Leases - Narrative (Details) $ in Millions	3 Months Ended	12 Months Ended			15 Months Ended
Leases - Narrative (Details) $ in Millions	Dec. 31, 2023 USD ($)	Sep. 30, 2025 USD ($) ft² option	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2024 USD ($)	Jun. 29, 2025 ft²
Lessee Lease Description [Line Items]
Short-term lease cost \| $		$ 0.0	$ 0.0	$ 1.4
Corporate Headquarters In Pasadena \| California
Lessee Lease Description [Line Items]
Office space leases (in sq ft) \| ft²		49,000
Corporate Headquarters In Pasadena \| California \| Colorado Owner, LLC
Lessee Lease Description [Line Items]
Number of options to renew \| option		1
Operating lease renewal term		5 years
Research Facility in San Diego \| California
Lessee Lease Description [Line Items]
Office space leases (in sq ft) \| ft²		144,000
Operating lease renewal term		10 years
Lease term		15 years
Proceeds from additional tenant improvement allowance \| $	$ 3.1				$ 30.8
Research Facility in San Diego \| California \| Maximum
Lessee Lease Description [Line Items]
Number of options to renew \| option		1
Research Facility in Madison \| Wisconsin
Lessee Lease Description [Line Items]
Office space leases (in sq ft) \| ft²		110,956				107,000
Number of options to renew \| option		2
Operating lease renewal term		5 years