Income Taxes - Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Unrecognized Tax Benefits [Roll Forward]
Beginning balance of unrecognized tax benefits	$ 16,613	$ 14,536	$ 3,481
Gross increase for prior period tax positions	1,160	654	9,495
Gross decrease for prior period tax positions	0	0	(1,489)
Gross increase for current period tax positions	4,379	3,415	3,049
Lapse of statue of limitations	0	(1,992)	0
Ending balance of unrecognized tax benefits	$ 22,152	$ 16,613	$ 14,536

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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-Topic 740
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-Name Accounting Standards Codification
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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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