CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (PARENTHETICAL) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Statement of Stockholders' Equity [Abstract]
Postretirement benefit adjustment, tax	$ 4	$ 40	$ 99

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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