Goodwill and Intangible Assets - Components of Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Finite-Lived Intangible Assets [Line Items]
Cost	$ 326,189	$ 331,606
Accumulated Amortization	165,498	145,072
Net Book Value	160,691	186,534
Patents
Finite-Lived Intangible Assets [Line Items]
Cost	1,226	1,242
Accumulated Amortization	1,077	1,002
Net Book Value	149	240
Completed Technology
Finite-Lived Intangible Assets [Line Items]
Cost	74,361	75,527
Accumulated Amortization	37,029	32,383
Net Book Value	37,332	43,144
Trademarks and Trade Names
Finite-Lived Intangible Assets [Line Items]
Cost	424	424
Accumulated Amortization	56	33
Net Book Value	368	391
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Cost	681	681
Accumulated Amortization	391	249
Net Book Value	290	432
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Cost	249,277	253,486
Accumulated Amortization	126,725	111,159
Net Book Value	122,552	142,327
Other Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Cost	220	246
Accumulated Amortization	$ 220	$ 246