Goodwill and Intangible Assets Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 117,538	$ 58,026
Finite-Lived Intangible Assets, Accumulated Amortization	(31,919)	(18,669)
Intangible Assets, Net (Excluding Goodwill)	85,619	39,357
Amortization of Intangible Assets	13,191	6,424	$ 3,950
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	13,683
Finite-Lived Intangible Assets, Amortization Expense, Year Two	13,153
Finite-Lived Intangible Assets, Amortization Expense, Year Three	12,810
Finite-Lived Intangible Assets, Amortization Expense, Year Four	12,370
Finite-Lived Intangible Assets, Amortization Expense, Year Five	12,030
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	21,573
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	15,262	7,754
Finite-Lived Intangible Assets, Accumulated Amortization	(2,891)	(1,741)
Intangible Assets, Net (Excluding Goodwill)	$ 12,371	$ 6,013
Trademarks and Trade Names [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	5 years
Trademarks and Trade Names [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years	20 years
Technical Library
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 400	$ 400
Finite-Lived Intangible Assets, Accumulated Amortization	(161)	(141)
Intangible Assets, Net (Excluding Goodwill)	$ 239	$ 259
Technical Library | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years	20 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 96,879	$ 46,449
Finite-Lived Intangible Assets, Accumulated Amortization	(24,021)	(14,900)
Intangible Assets, Net (Excluding Goodwill)	$ 72,858	$ 31,549
Customer Relationships [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	6 years	6 years
Customer Relationships [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years	15 years
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 40	$ 40
Finite-Lived Intangible Assets, Accumulated Amortization	(25)	(17)
Intangible Assets, Net (Excluding Goodwill)	$ 15	$ 23
Noncompete Agreements [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	5 years
Construction Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 4,957	$ 3,383
Finite-Lived Intangible Assets, Accumulated Amortization	(4,821)	(1,870)
Intangible Assets, Net (Excluding Goodwill)	$ 136	$ 1,513
Construction Contracts [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year	1 year