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Goodwill and Intangible Assets Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2023	Sep. 30, 2024
Goodwill [Line Items]
Goodwill, beginning	$ 93,960
Goodwill, Acquired During Period	13,870
Goodwill, ending	107,830
Goodwill, Impaired, Accumulated Impairment Loss	(6,976)		$ (6,976)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		$ 13,045
Communications [Member]
Goodwill [Line Items]
Goodwill, beginning	2,816
Goodwill, Acquired During Period	9,520
Goodwill, ending	12,336
Residential [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	0
Goodwill, ending	51,370
Infrastructure Solutions [Member]
Goodwill [Line Items]
Goodwill, beginning	39,774
Goodwill, Acquired During Period	4,350
Goodwill, ending	44,124
Commercial and Industrial [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	0
Goodwill, ending	$ 0

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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