Goodwill and Intangible Assets Goodwill (Details) $ in Thousands	9 Months Ended
Jun. 30, 2020 USD ($)
Goodwill [Line Items]
Goodwill	$ 50,622
Goodwill, Acquired During Period	9,862
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments	0
Goodwill	60,484
Commercial and Industrial [Member]
Goodwill [Line Items]
Goodwill	6,976
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments	0
Goodwill	6,976
Residential [Member]
Goodwill [Line Items]
Goodwill	10,018
Goodwill, Acquired During Period	5,946
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments
Goodwill	15,964
Infrastructure Solutions [Member]
Goodwill [Line Items]
Goodwill	30,812
Goodwill, Acquired During Period	3,916
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments	0
Goodwill	34,728
Communications [Member]
Goodwill [Line Items]
Goodwill	2,816
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments	0
Goodwill	$ 2,816

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of divestiture 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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