Income Taxes - Summary of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Income Tax Disclosure [Abstract]
U.S. federal statutory income tax	21.00%	21.00%	21.00%
State income taxes, net of federal tax benefit	0.40%	8.60%	7.00%
Tax credits	6.80%	0.00%	0.00%
Permanent and other items	(4.60%)	(1.70%)	0.00%
Non-deductible compensation	(4.60%)	0.00%	0.00%
Foreign-derived intangible income deduction	1.20%	0.00%	0.00%
Stock compensation	(1.10%)	(1.70%)	1.30%
Valuation allowance	(20.50%)	(28.40%)	(29.30%)
Effective income tax rate	(1.40%)	(2.20%)	0.00%

Effective Income Tax Rate Reconciliation, Nondeductible Expense, Compensation, Percent

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-12

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Percentage of reported income tax benefit from difference to income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to foreign-derived intangible income (FDII).

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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