Goodwill and other Identifiable Intangible Assets (Amortization Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 22,409	$ 25,106	$ 27,203
2026	28,504
2027	28,504
2028	28,296
2029	26,412
2030	26,009
Cost of Sales and General and Administrative Expense [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 22,141	$ 24,552	$ 25,226

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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