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Goodwill and Other Intangible Assets - Narrative (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2022 USD ($)	Sep. 30, 2022 USD ($) segment	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Finite-Lived Intangible Assets [Line Items]
Number of operating segments \| segment		3
Goodwill and intangible asset impairment	$ 0
Goodwill		$ 3,524,000,000	$ 3,625,900,000
Amortization of intangible assets		112,300,000	65,900,000	$ 50,200,000
Estimated amortization expense in 2022		110,200,000
Estimated amortization expense in 2023		107,100,000
Estimated amortization expense in 2024		103,800,000
Estimated amortization expense in 2025		102,700,000
Estimated amortization expense in 2026		95,800,000
Sensia
Finite-Lived Intangible Assets [Line Items]
Goodwill		315,900,000
Software products
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ 9,400,000	$ 11,900,000	$ 10,200,000