Goodwill and Intangible Assets Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Goodwill [Line Items]
Goodwill, beginning	$ 92,395	$ 53,763
Goodwill, Acquired During Period		38,632
Impairment expense	0	0	$ (6,976)
Goodwill, ending	92,395	92,395	53,763
Communications [Member]
Goodwill [Line Items]
Goodwill, beginning	2,816	2,816
Goodwill, ending	2,816	2,816	2,816
Residential [Member]
Goodwill [Line Items]
Goodwill, beginning	51,370	16,219
Goodwill, Acquired During Period		35,151
Goodwill, ending	51,370	51,370	16,219
Infrastructure Solutions [Member]
Goodwill [Line Items]
Goodwill, beginning	38,209	34,728
Goodwill, Acquired During Period		3,481
Goodwill, ending	38,209	38,209	34,728
Commercial and Industrial [Member]
Goodwill [Line Items]
Goodwill, beginning	0	0
Impairment expense			(6,976)
Goodwill, ending	$ 0	$ 0	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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