Derivatives - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Open Forward Foreign Currency Contract [Line Items]
Net gain (loss) related to the fair value hedge	$ (4,557)	$ 4,598
Collateral pledged	4,890	650
Interest Rate Swap
Open Forward Foreign Currency Contract [Line Items]
Net gain (loss) related to the fair value hedge	$ (4,557)	$ 4,598