Goodwill and Intangible Assets Goodwill (Details) $ in Thousands	6 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Line Items]
Goodwill	$ 50,622
Goodwill, Acquired During Period	9,920
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments	0
Goodwill	60,542
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	6,014
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments
Goodwill	16,032
Infrastructure Solutions [Member]
Goodwill [Line Items]
Goodwill	30,812
Goodwill, Acquired During Period	3,906
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Purchase Accounting Adjustments	0
Goodwill	34,718
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 increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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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