Supporting Financial Information - Goodwill (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2025	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Goodwill	$ 138,161	$ 138,161
Changes in goodwill	$ 0

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details